That human knowledge which is called rational is, in turn, imperfect knowledge because it is vague, uncertain, shifting, and laborious. Add the intellectual knowledge of divine minds, which the theologians call angels. Even that is imperfect knowledge, at least because it seeks outside itself what it does not possess fully within itself, i.e., the light of truth which it lacks, and by which is is perfected.
the life of the angels is not perfect. Unless the vivifying ray of divine light constantly warmed it, it would all fall into nothingness. The same is true of other things. Therefore, when you say that God is knowing and living, notice first that the life and cognition which are ascribed to him are understood as free from all these imperfections, but this is not enough. There remains another imperfection.