Anselm's impassible God

Anselm himself, relying on Platonic views about perfection, uses such arguments to defend the view that God is “impassible” (cannot be affected by anything outside of himself), changeless, timeless, and utterly simple. Reflection on God’s attributes using the method of what has come to be called “perfect being theology” is still very much alive. However, some contemporary philosophers, while still employing perfect being theology, have questioned some of Anselm’s Platonic ideas about what counts as a perfection. For example, is it really a perfection not to be able to be affected by what else happens? Might it be that a God who is capable of interacting with and responding to his creatures is actually more perfect than a God who is incapable of change? It seems particularly important to think about how a God who chose to become incarnate as a human being might change and interact with his creatures.—Evans, A History of Western Philosophy, 160