(ibid)It must necessarily be maintained that the angels are incorruptible of their own nature. The reason for this is, that nothing is corrupted except by its form being separated from the matter. Hence, since an angel is a subsisting form, as is clear from what was said above (2), it is impossible for its substance to be corruptible. For what belongs to anything considered in itself can never be separated from it; but what belongs to a thing, considered in relation to something else, can be separated, when that something else is taken away, in view of which it belonged to it. Roundness can never be taken from the circle, because it belongs to it of itself; but a bronze circle can lose roundness, if the bronze be deprived of its circular shape. Now to be belongs to a form considered in itself; for everything is an actual being according to its form: whereas matter is an actual being by the form. Consequently a subject composed of matter and form ceases to be actually when the form is separated from the matter. But if the form subsists in its own being, as happens in the angels, as was said above (2), it cannot lose its being. Therefore, the angel's immateriality is the cause why it is incorruptible by its own nature.
A token of this incorruptibility can be gathered from its intellectual operation; for since everything acts according as it is actual, the operation of a thing indicates its mode of being. Now the species and nature of the operation is understood from the object. But an intelligible object, being above time, is everlasting. Hence every intellectual substance is incorruptible of its own nature. |
