Thursday, December 13, 2007

Worst Blog Post Title of the Month

It has to be this: "Just Say No to Ecumenism".

Because of course Jesus was just kidding when he prayed that we might be one (and for those who want to pretend that some ridiculous "invisible" oneness is sufficient for this, the Lord went on: "that the world may believe that thou hast sent me.")

Shame on all of us for our disunity, but shame, shame on anyone for actually preferring that disunity!

Friday, December 7, 2007

Catholic Theology is not Protestant Systematic Theology

The subject of this post may seem like a no-brainer, but I'm not specifically talking about a comparison of the content of the two different types of theology.

When I came in the course of reading the Summa Theologica to the discussion of transubstantiation in the Eucharist, I realized something about the nature of Catholic theology. I found St. Thomas' explanation of this subject to be either absurd or - more likely - incomprehensible. But does my inability to grasp his explanation mean that the doctrine is false? By no means. The doctrine is true regardless of my ability understand it, and - more to the point of the present post - it is true regardless of my ability to understand the explanation by St. Thomas. It is true regardless of whether he was able to explain it in a fashion that I could have grasped.

And so I realized that Catholic theology is different than Protestant systematic theology in a significant way. Catholic theology is an attempt to make sense out of the truth: to explain it in comprehensible terms. This is one reason, it seems to me, why modern Catholic theology can differ so dramatically from (for example) the Scholastic attempts, and yet still be entirely orthodox.

Maybe that sounds dumb, or trivially obvious to brighter wits than mine or to life-long Catholics. But for this convert it was something of an epiphany. Because this is not how theology is done in the circles whence I came. Among Protestants (at least of my old stripe) theology is primarily "systematic" - that is, it consists of systematizing the Bible by collating various related verses in order to present what the Bible teaches on some given subject(s) or other. This is rather different from the Catholic model of explaining the Faith, but perhaps the difference makes sense. For the Protestant there is no rule of faith except the Bible, and so if you want to know what the truth is on a given subject, you must resort to ... collating the various verses that seem to relate to it: in other words, systematizing them.

Now whereas the Catholic theologian attempts to explain the Faith, the Protestant theologian's task seems to be more along the lines of (so to speak) defining the faith. What I mean is that since the Bible is "raw material" that doesn't exactly present its doctrine in a systematic fashion, that becomes a primary task of the theologian. The problem is, of course, that different theologians will differ on how things ought to be systematized. They will select different verses and passages as being of greater or lesser importance; they will declare one passage rather than another to be the keystone by which other verses ought to be understood; etc. The consequence is that "the faith" - meaning the system of doctrine - that they find in the Bible will vary considerably, depending upon the personal commitments of the theologians (are they Calvinist? Methodist? Anglican? Lutheran?).

In contrast you have Catholic theologians, who agree (presuming that they are orthodox) on the content of the Faith but who sometimes disagree on how to explain it. Thus you may have the theology of St. Thomas on the one hand, and you can have (for example) the theology of Cardinal Ratzinger/Pope Benedict on the other. Both are orthodox, and yet their theologies are dramatically different. I think that at least partly this can be explained on the basis of their different audiences. St. Thomas wrote for new students of scholastic theology; the Pope writes for 20th/21st century men. How their audiences think about things vary wildly; consequently how the two theologians present the faith to them also must be very different.

I was inspired to write about this subject by something the Crimson Catholic wrote today. It wasn't the primary purpose of his post, which has to do with differences between Byzantine and Latin theology, but in the course of it he said this:
In that regard, ISTM that the whole West (e.g., Ambrose, Hilary, Simplicianus, Jerome) followed Origen in method but not conclusions, examining the applicability of philosophical concepts to Christianity but also being willing to admit where the concepts were inadequate. If they reached a wrong dogmatic conclusion, rather than discarding the method entirely, the West was content to point out that they had made an error or taken some particular idea too far. In other words, if some philosophical approach reached a wrong conclusion, they were content to discard the approach. Because they weren't married to this one notion of philosophical knowledge, they could be eclectic in philosophy. That versatility, perhaps best exemplified by Augustine, characterized Western Christian thought and (I would argue) Western scientific thought all the way to the present day.

What that enabled theologically was exposition of dogma. The theological conclusions had authority, so the Fathers were authorities regarding their conclusions, but like Aristotle with Plato, their philosophical explanations could be criticized and improved, opening the possibility of development. Hence, you could have disputations with authorities; even respected authorities were not immune to dialectical criticism. There was a Glossa Ordinaria; there were commentaries on the Sentences. In the case of theological authorities (like Scripture or the Pope), there was still utility in theological method in terms of conceptual improvement of one's own understanding, effectively giving more clarity or effect to the theological authority. ... In short, there was a gap between how something was examined qua theological authority and how it was examined qua philosophical authority, and the philosophical understanding was always revisable even if the fact of the dogmatic authority was not, much like the way one can revise a scientific explanation without changing the fact of the experimental data. Note that this is a separate issue from the formality of dogmatic authority addressed by the canonists; the interaction (and confusion) of those concepts is a whole 'nother can of worms.
Exactly! Or rather - this is exactly the sort of thing I mean. Dogmatic authority is distinct from philosophical authority. So the terms on which St. Thomas described the Faith - a scholastic, Aristotelian framework - can differ from the terms employed by Ratzinger (I hope it's fair to describe them summarily as philosophically modern - whether that is correct or not, it seems very clear to me that apart from some Thomoistic sympathies, Ratzinger's philosophical framework is emphatically not Thomistic).

Now I think it's likely that some Protestants suppose that the philosophic framework used by Catholic theologians cannot change: so that some of them might suppose that the Vatican II/post-Vatican II Church has broken with the past (as Turretinfan suggested in discussion) because the way that the Church explains the Faith has changed in some ways. No. The Faith has not changed. It is the same. The language has changed, and in some cases the understanding of some things may have advanced, and the way that the Faith is explained may be different, but the Faith itself is the same. Failure to understand these things is fundamentally a failure to understand Catholic theology and its relationship to the Catholic Faith.

Perhaps it is understandable in a certain fashion when they make this mistake, because conservative Protestant theology has (again, in the tradition of which I was part at least) a rather rigidly specified philosophical outlook. You have to get your theology from the Bible; you have to use a particular hermeneutic (grammatical-historical) when getting it from the Bible. When you read a theology, you are reading someone's attempt at spelling out what he thinks the teaching of the Bible is. But you can't approach Catholic theology like that. Catholic theology doesn't define the Faith in the way that we might say that Protestant theologies "define the faith". Catholic theology explains the Faith. Some explanations are better than others, and some explanations may be better suited to one era than another. In either case, the Faith itself remains unchanged.

Monday, December 3, 2007

Last Call (for now) on Vatican II's Continuity (with Leo)

I think that the fundamental bone of contention might possibly be found in this nugget, mined from here:
If a MAN is validly baptized AND accepts the Catholic Faith, then he is a Catholic, and thus a Christian, but only Catholics are Christians as already explained, so that only those adults who both have baptism and hold the Christian faith can be rightly called Christian.
Leo says this in response to my point 4 here. His argument (as he elucidates more fully in the comment; and if I misrepresent him here, I trust that he will chime in and correct me!) is that a baptized non-Catholic either becomes a Catholic by seeking out a true knowledge of the Faith and converting, or else he ceases to be a Christian.

I deny this.

This subject is intrinsically related to the question of invincible ignorance. It seems to me that Leo's comments (not just the snippet above, but generally on this subject) make no allowance for the subjective reality of where people find themselves. In the first place, the Catholic faith does not oblige anyone to be an expert in doctrine. This is the whole point of implicit faith. How can an uninformed Catholic remain a Catholic in good standing if he remains uninformed? It would seem that Leo allows for them to be saved despite their material ignorance, but he does not extend this same charity to the non-Catholic Christian. I submit that this is a distinction without a difference when it comes to ignorant believers, and consequently it is an invalid distinction. Hence, if Catholics may be saved while ignorant of Catholic doctrine, so may Protestants. We are not saved by by right belief per se, but by Christ. And just as there are ignorant Catholics who nevertheless would believe the truth if they knew it, there are Protestants who are zealously and singlemindedly devoted to the pursuit of truth - who just happen to be badly mistaken. And it is an error to suppose that true devotion to the truth absolutely, positively results in acquisition of the truth always and every time. Witness: St. Thomas, who got the Immaculate Conception wrong just because he considered only the theories of grace before conception and after conception, but not at the moment of conception.

[EDIT: I am not saying above that what we believe does not matter. If I believed that I would not be Catholic! But there is a valid distinction to be made between the efficient cause of our salvation - which is Christ - and the material causes, like our holding to the Faith and living a holy life. If material right belief is a prerequisite, then implicit faith is destroyed and even St. Thomas is doomed since he denied the Immaculate Conception!]

But if St. Thomas of all people can get it wrong on something, despite being fully qualified in both theology and philosophy and the doctrine of the Church...then I think it is a certainty that the far less educated Protestant of today can likewise have a zealous devotion to the truth while at the same time coming to wrong conclusions.

In the second place, the average Protestant today is entirely and completely ignorant of what the Catholic Church teaches. Leo suggests that this ignorance is inexcusable (ibid., point seven), but that is so only if they know that they should not be. Two subpoints here. A: They have been taught an entirely different concept of salvation, and that concept does not in any way include the Catholic Church. So how are they supposed to get the idea that they are obliged to learn about the Church in order to be saved??? B: They have been taught, negatively, that the Catholic Church teaches a false gospel. So how are they supposed to get the idea that this isn't true?

One answer to that is that some Catholic or other must tell them. But what if these Protestants don't have contact with Catholics? And what if the Catholics they meet do a lousy job of trying to persuade them? Or what if the Catholics do a reasonably good job, but the Protestant can't understand because he is incapable of grasping the Catholic's arguments? What if the Protestant has counter-arguments ready to hand that he sincerely thinks entirely refute the Catholic's view? None of these circumstances mean in any way that the Protestant is insincere, or that he would hate the truth if he knew it. It simply means that he doesn't know it.

Even the brightest minds can miss the truth (again: witness St. Thomas and the Immaculate Conception). But if sincere and gifted people can miss the truth without condemnation, then how much more those who are less gifted? How much more those who simply don't have time to seek out the truth because they work two jobs, or are single parents, and who only barely manage to make it to their congregation on Sundays for worship? It's not credible to say that such people are guilty in their circumstances of failing to seek out the truth. They do the best that they can...or at any rate, that is how we ought charitably to assess their situations, it seems to me, until we have definite evidence to the contrary.

But Vatican II demands no more than this: the presumption that Protestants are fellow Christians until proven otherwise. Material heresy does not ipso facto exclude them, and ignorance of their error does not ipso facto condemn them.

And this is precisely why I say that Vatican II is consistent and continuous with the prior Magisterium: it affirms the distinction of material vs. formal heresy; it affirms the validity of heretical baptism; it affirms that people may be invincibly ignorant. None of these are "new" ideas.

And that is all I've got to say about this subject for the time being, other than to thank Leo for his gracious bearing (outstripping my own, for which I apologize) during our conversation.

Sunday, December 2, 2007

Trying to Resolve the Issue With Leo

My perspective on the subject of Vatican II's declarations concerning Protestants may be defined this way:
  1. Material heretics are not under the same condemnation as formal heretics (see here, for example, where it says of formal heretics that they are subject to damnation, while material heretics are not, as indicated by the accompanying quotations from St. Augustine and Pope Pius IX and as discussed earlier here). This distinction is confirmed in the words of Vatican II quoted here: "The children who are born into these Communities and who grow up believing in Christ cannot be accused of the sin involved in the separation..." (UR 3), which is really nothing more than a restatement of the policy identified by St. Augustine in the quotation from the Catholic Encyclopedia; hence it seems that to deny the validity of the distinction between material and formal heresy would be contrary to the practice of the Church over the last 16 centuries.
  2. Valid baptisms occur outside the Catholic Church. This should be completely non-controversial.
  3. A valid baptism outside the Catholic Church accomplishes what a valid baptism within the Church does. If it did not, it would not be valid in the first place; in the second, the Church would not accept the Trinitarian baptisms of heretics as valid. But the Church has done so since at least the Donatist controversy in the 4th century, so that to deny this would be to deny 17 centuries of Church teaching and practice.
  4. If a man has been validly baptized, then he is a Christian: after all, this is precisely what baptism accomplishes. If he is not a Christian, then he has not been validly baptized - which would be a contradiction of point three.
  5. Protestants today are material heretics, not formal heretics. This should be obvious from the fact that they cannot be formal heretics by virtue of the fact that they have never been under the formal jurisdiction of the Catholic Church. Simply holding to an error that contradicts the faith does not ipso facto make one a formal heretic. Again, see the Catholic Encyclopedia discussion above, which (among other things) clearly establishes that material heretics are not formal heretics even under color of ecclesiastical law (and if they were, the distinction between the types of heresy would be destroyed - which would be irrational).
  6. Virtually all Protestants today are validly baptized. There are exceptions among some groups, I think but there is no credible reason to dispute the validity of the general validity of their baptisms. Of course it may be true in any specific instance to have doubts, but that has no bearing upon the validity of the presumption that, generally speaking, Protestant baptisms are valid.
  7. Because they are not formally heretical, and because they are validly baptized, there is absolutely nothing that prevents them from being understood to be Christians, and consequently it is certainly valid to make the presumption that they are in fact Christians - and consequently our brothers in Christ.
That's basically the substance of my argument. As far as I can tell, it is consistent with what Vatican II has said. The two points that it hinges upon are that Protestants are not formally heretical, and that their baptisms are valid. There is no valid reason to doubt either of these points - not rationally, and not in the Church's history, either.

Perhaps the sticking point is that historically Protestantism presents something that had never occurred before in the Church's history (assuming that I know enough history to be speaking accurately here): prior to the Reformation, heretical groups who were expelled from the Church vanished. But that is not the case with the Protestants. They haven't vanished. And if St. Augustine's rule about how to treat the children of heretics had validity with the first generation of children, how much more would it be valid with subsequent generations even more distantly removed from the original formal error? I contend that it is an error to consider them to be formally heretical - and Vatican II denies that they are. But if they are not, then it would be an error to treat them as though they were formally heretical - and Vatican II affirms that they should not be.

My affirmation is that Vatican II was a valid ecumenical Council. On the particular point of the Catholic's relationship to Protestants, I believe that the Council's teaching is rational, coherent, and consistent with the Church's teaching throughout the ages - as demonstrated above. Anything that seems to suggest otherwise must be talking not about material heretics, but rather about those who are formally heretical - and consequently it does not apply to Protestants.

Ratzinger - Luther and the Secularization of Love

Here is a striking passage from Cardinal Ratzinger's Introduction to Christianity. Before I go too far, I should mention that you can read this passage online here (it starts on p. 208 and concludes on p.209, though I'm not reproducing all of it in this post); I'm astonished that Ignatius has given permission to Google for this. So you can read this portion at Google, but the book is excellent enough that you ought to buy it.

It has to do with one of the effects of Luther's soteriology, and I think that it goes to show that ideas have consequences.
The profession of faith in Christ demanded by the Lord when he sits in judgment is explained as the discovery of Christ in the least of men, in those who need my help. From here onward, to profess one's faith in Christ means to recognize the man who needs me as the Christ in the form in which he comes to meet me here and now; it means understanding the challenge of love as the challenge of faith. The apparent reinterpretation here - in Matthew 25 - of the christological profession of faith into the unconditionality of human service and mutual help is not to be regarded, after what we have said, as an escape from otherwise prevailing dogma; it is in truth the logical consequence of the hyphen between Jesus and Christ and, therefore, comes right from the heart of Christology itself. For this hyphen - let me repeat - is at the same time the hyphen between faith and love. Therefore it is also true that faith that is not love is not really a Christian faith; it only seems to be such - a fact that must redound both against any doctrinalistic misunderstanding of the Catholic concept of faith and against the secularization of love that proceeds in Luther from the notion of justification exclusively by faith (p. 209, bold added; italics in original).
Yowza. But what does he mean by this "secularization of love" that is a consequence of Luther's soteriology? He explains a bit more in the footnote.
Hacker shows there with an abundance of textual references that Luther as a reformer (i.e., from about 1520 onward) assigns love to the "outward life", to "the use of the second table", to life not with God but "with men", and thus to the realm of the profane, to what is called today "pure worldliness", and therefore to the "righteousness of the law". He thus secularizes it and excludes it from the realm of grace and salvation. Hacker is thereby able to demonstrate convincingly that Gogarten's [Gogarten was a German theologian - RdP] program of secularization can quite rightly claim to be based on Luther. It is clear that at this point Trent had to draw a firm dividing line and that where the secularization of love is retained the dividing line continues to run as it did before (emphasis added).
Now if I understand him correctly, he's saying that with his doctrine of justification by faith alone, and a concomitant denial of the necessity of love for neighbor, Luther moved the theological virtue of charity to the category of "righteousness of the law" - and consequently divorced it from having any essential significance with regard to salvation. I don't know anything about Gogarten, but here is a brief article about him from Time magazine in 1966; in it Gogarten is said to have appealed to Luther as the forerunner of his secular theology. It seems clear from the above that Ratzinger considers Gogarten's work to be contrary to the Catholic understanding of the faith, inasmuch as it (apparently) wrongly drives a wedge between what we believe as Christians and our relationships with our fellow men. If love for God and neighbor are the two greatest commandments, then I can perhaps understand how Luther might get the idea - if they are reckoned to be commandments - that they fall under the division of the "righteousness of the law" that he rejects; but it seems rather clear from Mt. 25 (as the cardinal indicates above) that this charity is rather more important than an option, but rather is at the root of the judgment that we shall face. Our actions matter.

Saturday, December 1, 2007

Continuity of Vatican II

Recently Leo disagreed with my statement that the average Protestant must be understood to be the Catholic's brother in Christ. This is really nothing more than a rough quote from Unitatis Redintegratio 3:
The children who are born into these Communities and who grow up believing in Christ cannot be accused of the sin involved in the separation, and the Catholic Church embraces upon them as brothers, with respect and affection. For men who believe in Christ and have been truly baptized are in communion with the Catholic Church even though this communion is imperfect. The differences that exist in varying degrees between them and the Catholic Church-whether in doctrine and sometimes in discipline, or concerning the structure of the Church-do indeed create many obstacles, sometimes serious ones, to full ecclesiastical communion. The ecumenical movement is striving to overcome these obstacles. But even in spite of them it remains true that all who have been justified by faith in Baptism are members of Christ's body, and have a right to be called Christian, and so are correctly accepted as brothers by the children of the Catholic Church.
It seems to me that what I've previously written on the subject of formal vs. material heresy is entirely consistent both with this quotation and with what has been held throughout the Church's history. UR 3 here is really not saying anything different about the children of formal heretics than was said by St. Augustine. The Catholic Encyclopedia of 1917 says essentially the same thing about material heretics, as I pointed out in that post.

Leo objected again - apparently rather strongly, though I meant no offense by it at all - when I pointed out that his opinion seemed to be contrary to what VII says in UR 3 and asked whether he agreed with the latter. I deliberately used the word "seemed" because I have no certain idea whether he agrees with VII on this or not. There are at least two ways that confusion could be generated here: either I could have misunderstood him, or he might have - quite unintentionally - either presented his view in a confusing or incomplete manner, so that it might seem to suggest that he believes something that he really doesn't. Hence my question.

Leo's response was to unload a large batch of quotations from various popes and theologians and to try and turn my question back upon me, suggesting that I was at variance with them.

Unfortunately this wasn't really an answer to my question, although perhaps one may infer an answer from it (and in the absence of a further clarification from him, I have inferred that he disagrees with UR 3; I would be happy to be mistaken about that).

But the issue that arises from Leo's comments has to do with the continuity of Vatican II with the teaching of the Catholic Church throughout history. It appears (and I will say no more than that it is an appearance, absent a clear statement from him about it) that Leo thinks that Vatican II has broken with the past, so that its doctrine (on this point at least) runs contrary to what the Church has always taught.

I disagree with that idea. In the first place, I think that my heresy post and my comments attached to it adequately show the continuity of Vatican II with the past. Secondly, I think that the whole subject raises the question: who is the authentic interpreter of the Magisterium's declarations? The answer must be that the Magisterium is its own authentic interpreter: it must tell us what it means by what it has said, and that goes not only for modern or recent times but for anything it has ever said. This should be entirely non-controversial for the Catholic.

The consequence of this in the present context is that if it seems to me that some past statement of the Magisterium is in conflict with a new one, either I have failed to properly understand things, or I'm missing some facts, or I am simply wrong. I do not possess either the competence or the authority to dictate for myself whether the Magisterium has been consistent with itself. Indeed, the very question is absurd: the Church as the living voice of Jesus Christ, with Christ her Head forming the totus Christus, cannot possibly err on matters of faith and morals. So I am forced inevitably to conclude that of course Vatican II is continuous with the Church's past, and if it seems otherwise to me, then of course I am mistaken, either through inadequate or erroneous understanding of the facts, or through fallacious reasoning.

I do not offer this post in the hope of influencing Leo's outlook on things (in fact, since I'm not even sure what his view is on the matter of Vatican II's continuity apart from some explicit statement by him, it might be totally unnecessary even to try to influence him). I'm not going to try and work through the quote-dump contained in his comments. He seems to think that they contradict Vatican II, and apparently he prefers to conclude that Vatican II is somehow wrong on the matter. I deny both of these ideas (whether they represent his position or not). I refer the reader to Dr. Michael Liccione's article "Development and Negation", perhaps especially the section "Extra ecclesiam nulla salus", for more on this subject.

Divine Simplicity

I've read (which is to be distinguished from having completely understood) a number of disputes about this topic between Catholics (who affirm it) and Orthodox (who, if I understand them correctly, deny it). The fact that I am posting on this subject should not be construed to suggest that I comprehend it very well, and if someone wishes to quarrel about it, they're going to get a better debate partner from someone like Dr. Michael Liccione. Nevertheless, St. Thomas' account is compelling to me, and of course I'm happy to stand with the Catholic Church on this question :-)

Now, with that disclaimer out of the way...

God is absolutely simple: he is not a composite being possessed of anything that might be construed as "parts". This is no new idea with St. Thomas; it is discussed by St. Augustine in De Trinitate VI (it might be worth noting that the New Advent page to which I'll be linking preserves an apparent typo in the edition of ST that they use; it refers to Book IV of De Trinitate for a quotation used by Aquinas, but it seems that it should have been Book VI: a simple transposition).
The absolute simplicity of God may be shown in many ways.

First, from the previous articles of this question. For there is neither composition of quantitative parts in God, since He is not a body; nor composition of matter and form; nor does His nature differ from His "suppositum"; nor His essence from His existence; neither is there in Him composition of genus and difference, nor of subject and accident. Therefore, it is clear that God is nowise composite, but is altogether simple.

Secondly, because every composite is posterior to its component parts, and is dependent on them; but God is the first being, as shown above (2, 3).

Thirdly, because every composite has a cause, for things in themselves different cannot unite unless something causes them to unite. But God is uncaused, as shown above (2, 3), since He is the first efficient cause.

Fourthly, because in every composite there must be potentiality and actuality; but this does not apply to God; for either one of the parts actuates another, or at least all the parts are potential to the whole (ST Q3 A7).
By way of observation on just one of the implications of this: we must understand all passages of the Scripture which speak of God's "wrath" as speaking figuratively. For if our actions can really cause God to become angry, then he stands in some sort of potentiality towards the creation, so that our actions would constitute a cause eliciting an effect in God - to make him angry. But that is absurd. So we have be cautious in what we attribute to God from our reading of the Bible.

Existence and Essence in God

To talk about what I am is different than to talk about the fact that I am. In philosophical terms, this is the distinction between essence and existence. But this distinction does not hold when we talk about God, as though they are actually separate things in him the way that they are in us.
God is not only His own essence, as shown in the preceding article, but also His own existence. This may be shown in several ways.

First, whatever a thing has besides its essence must be caused either by the constituent principles of that essence (like a property that necessarily accompanies the species--as the faculty of laughing is proper to a man--and is caused by the constituent principles of the species), or by some exterior agent--as heat is caused in water by fire. Therefore, if the existence of a thing differs from its essence, this existence must be caused either by some exterior agent or by its essential principles. Now it is impossible for a thing's existence to be caused by its essential constituent principles, for nothing can be the sufficient cause of its own existence, if its existence is caused. Therefore that thing, whose existence differs from its essence, must have its existence caused by another. But this cannot be true of God; because we call God the first efficient cause. Therefore it is impossible that in God His existence should differ from His essence.

Secondly, existence is that which makes every form or nature actual; for goodness and humanity are spoken of as actual, only because they are spoken of as existing. Therefore existence must be compared to essence, if the latter is a distinct reality, as actuality to potentiality. Therefore, since in God there is no potentiality, as shown above (Article 1), it follows that in Him essence does not differ from existence. Therefore His essence is His existence.

Thirdly, because, just as that which has fire, but is not itself fire, is on fire by participation; so that which has existence but is not existence, is a being by participation. But God is His own essence, as shown above (Article 3) if, therefore, He is not His own existence He will be not essential, but participated being. He will not therefore be the first being--which is absurd. Therefore God is His own existence, and not merely His own essence (ST I Q3 A4).
We have to be careful about the way that we talk about God. St. Thomas points out (ST I Q3 A3 ad 1) that we the way that we acquire knowledge - from composite beings like ourselves - means that our language lends itself to talking about things as composite beings. But this is not true of God. He is not a composite being. He is absolutely simple. So although we may talk about what God is like in ways that might suggest that he has attributes and accidents after the manner of created things, we must remember that this is not how he is really.

God is a Spirit

Of course we know this most truly and certainly because it is the teaching of Scripture: "God is spirit, and they who worship him must worship in spirit and in truth" (John 4:24 CCD). But this is a truth that may also be arrived at by way of reason.
It is absolutely true that God is not a body; and this can be shown in three ways.

First, because no body is in motion unless it be put in motion, as is evident from induction. Now it has been already proved [ST I Q2 A3], that God is the First Mover, and is Himself unmoved. Therefore it is clear that God is not a body.

Secondly, because the first being must of necessity be in act, and in no way in potentiality. For although in any single thing that passes from potentiality to actuality, the potentiality is prior in time to the actuality; nevertheless, absolutely speaking, actuality is prior to potentiality; for whatever is in potentiality can be reduced into actuality only by some being in actuality. Now it has been already proved that God is the First Being. It is therefore impossible that in God there should be any potentiality. But every body is in potentiality because the continuous, as such, is divisible to infinity; it is therefore impossible that God should be a body.

Thirdly, because God is the most noble of beings. Now it is impossible for a body to be the most noble of beings; for a body must be either animate or inanimate; and an animate body is manifestly nobler than any inanimate body. But an animate body is not animate precisely as body; otherwise all bodies would be animate. Therefore its animation depends upon some other thing, as our body depends for its animation on the soul. Hence that by which a body becomes animated must be nobler than the body. Therefore it is impossible that God should be a body (ST I Q3 A1).

From this we see that it is not merely blasphemous and profane to say that God is or has a body. It is irrational.

Francis Schaeffer and Aquinas

Francis Schaeffer rather famously (well, among at least some evangelicals anyway; okay, maybe that doesn't exactly qualify as "famously", but work with me here) claimed that the descent of philosophy into existentialism and irrationality began with St. Thomas. We can see Schaeffer's idea summarized here:
Aquinas separated nature from grace in theology. The spiritual world and the earthly world became separated. The earthly world became what was "real" and the spiritual world was the "hypothetical."
The largest problem with this is that it's just plain nonsense. St. Thomas said nothing of the sort, and I can't conceive of any way that what he did say could rationally be construed like this. In the first place, he was an orthodox Christian, and to separate nature from grace smacks of Pelagianism. Secondly, it's irrational: God created us freely and without compulsion; hence creation was an act of grace from start to finish.

Thirdly, it seems that Schaeffer never bothered to read as far as the sixth article of the first question of the Summa Theologica. Because if he had, he would have realized that his construal of Aquinas was wrong.
The principles of other sciences either are evident and cannot be proved, or are proved by natural reason through some other science. But the knowledge proper to this science [theology] comes through revelation and not through natural reason. Therefore it has no concern to prove the principles of other sciences, but only to judge of them. Whatsoever is found in other sciences contrary to any truth of this science must be condemned as false: "Destroying counsels and every height that exalteth itself against the knowledge of God" (2 Corinthians 10:4-5) (ST I Q1 A6 ad 2).
St. Thomas says here that because the knowledge that is the subject of theology comes by revelation from God, it is consequently superior to the other sciences in the sense (among other ways that it is superior) that it is more certain. We attain to knowledge in the other sciences only with great difficulty: we may make errors of reason, so that we reach incorrect conclusions; on the other hand, we may draw valid inferences that are nevertheless false because the evidence we have at hand is inadequate. But revelation suffers from neither of these defects, and because it comes from God it cannot possibly be false because God does not lie, and his knowledge is perfect. This being the case, it rightly serves as the standard by which all the other sciences must be judged: so that, as he says, "Whatsoever is found in other sciences contrary to any truth of this science must be condemned as false." This being the case, it seems to me to be silly to say (as Schaeffer did) that Aquinas separated grace from nature. Nature is subject to judgment by revelation, as the saint says here.

Nevertheless, it must still be said that St. Thomas affirmed that reason can arrive at truth, and that it is not dependent upon theology to do so. To be sure, it is limited as to the scope and extent of the truth it can discover. Reason cannot discover those things that can only be known by faith, such as the fact that God is triune. It seems ridiculous to say that this affirmation of reason's (limited) power to discover truth in any way divorces nature and grace. To the contrary: what this means is that God has created us in such a way that we are well-suited for life in the world. Our senses and our minds reliably allow us to understand creation.

Far from being "hypothetical," one would be closer to the truth if he said that Aquinas considered the spiritual world to be more real than the physical world. To assert the contrary about him is either grossly ignorant or downright slanderous. Modern philosophy started with Descartes' rationalism, not with St. Thomas.

Minor Point of Historical Clarification

This may not be all that important a thing to point out, but it's still interesting to me. It has been common to suppose that the expert opinion of the Middle Ages held that the earth was flat. Well, here's St. Thomas, reporting a conclusion of science in the 13th century:
For the astronomer and the physicist both may prove the same conclusion: that the earth, for instance, is round: the astronomer by means of mathematics (i.e. abstracting from matter), but the physicist by means of matter itself (ST I Q1 A1 ad 2).
Yes, I know that they didn't have things straight about the earth's position relative to the sun, the galaxy, and so forth. Their science was flawed, but not quite as badly as many folks erroneously assume. On the one hand, they can certainly be excused: science is a cumulative enterprise, and it's unfair to criticize prior generations for failing to have grasped everything that we know today. On the other hand, it's worth noting that modern scientific knowledge is beholden to the experts of the past. "If I have seen further it is by standing on ye shoulders of Giants," said Isaac Newton. And does it need to be said that even our modern understanding of creation is both flawed and partial, however much we have corrected the errors of the past?