We know well enough, that God does not love or hate as we do; because, we love and hate mutably, but He loves and hates from an eternal and immutable nature; and hence it is, that accidents and passions do not pertain unto Him.Bondage of the Will, Section 101
If God's essence could change, a being more powerful than God would have to change it. It is true that we sometimes read of God 'repenting'; however, this is anthropomorphic language, which depicts the infinite, eternal, and unchangeable God, who is spirit, in human terms.Knowing Christ (38)