Medieval View of Order and Man's Place in Creation

By virtue of being created by God, there is an orderliness in creation; each species of things and every member of them is an essential part of the whole. But because God willed to make rational beings - viz., men and the angels - the potential for that orderliness to be turned on its head necessarily followed.

The first disruption of the 'rightness' of the creation had come with the fall of the devil and the other evil angels. As rational beings, they had received free will as a means for preserving their rightness. ... [The first disruption] happened in the disobedience of Satan. To 'restore the number that had been diminished by the fall of Satan,' the God of rightness and moral order created man. It was a long-established teaching, apparently based on the statement of the Septuagint (which was neither derived from the Hebrew nor carried over into the Latin) that 'he fixed the bounds of the peoples according to the number of the angels of God' [Dt. 32:8, LXX] that 'the number of the good angels, which was diminished after the fall of the evil angels, will be completed by the number of elect human beings, a number that is known only to God. ... [I]t was a widespread belief among theologians that God had made the human race because the rightness of the moral order required that the number of the blessed ordained by him be completed. [Pelikan, The Growth of Medieval Theology, 140]

It's interesting that this view of things springs from a reading in the Septuagint that's attested neither by the Hebrew nor the Vulgate, considering how Greek was not known by many Latins. I infer from this a confirmation of Pelikan's remark that this was a "long-established" idea, and must have pre-dated any significant linguistic division of the Church. Interesting - to me, anyway. :-)