If any one saith, that the good works of one that is justified are in such manner the gifts of God, as that they are not also the good merits of him that is justified; or, that the said justified, by the good works which he performs through the grace of God and the merit of Jesus Christ, whose living member he is, does not truly merit increase of grace, eternal life, and the attainment of that eternal life,-if so be, however, that he depart in grace,-and also an increase of glory; let him be anathema.
Two important observations for those who erroneously suppose that the Catholic Church teaches a so-called “works-based gospel:” First, the canon says that it’s the good works of “one that is justified” that are in view here: in other words, it relates to those who have already been justified. Secondly, they tell us that the good works of such a man merit increase of grace, not its initial reception. In short: they are talking about the good deeds of those who are already Christians.
Even so, they do not deny that a Christian’s good works are in fact gifts of God, as they have previously said in Chapter XVI of the Decree on Justification (which we have previously examined).
The Fathers of Trent are saying that how we live our lives as Christians really does matter, and they are condemning the error of some Protestants who falsely say otherwise. We are justified by grace alone, as Trent teaches us, but having been justified, we must then strive to live lives of holiness with God’s help.