Aquinas on God’s Immutability
God’s Immutability according To Aquinas.
“It is written, “I am the Lord, and I change not” (Malachi 3:6). _I answer that,_ From what precedes, it is shown that God is altogether immutable. First, because it was shown above that there is some first being, whom we call God; and that this first being must be pure act, without the admixture of any potentiality, for the reason that, absolutely, potentiality is posterior to act. Now everything which is in any way changed, is in some way in potentiality. Hence it is evident that it is impossible for God to be in any way changeable. Secondly, because everything which is moved, remains as it was in part, and passes away in part; as what is moved from whiteness to blackness, remains the same as to substance; thus in everything which is moved, there is some kind of composition to be found. But it has been shown above (Q. 3, A. 7) that in God there is no composition, for He is altogether simple. Hence it is manifest that God cannot be moved. Thirdly, because everything which is moved acquires something by its movement, and attains to what it had not attained previously. But since God is infinite, comprehending in Himself all the plenitude of perfection of all being, He cannot acquire anything new, nor extend Himself to anything whereto He was not extended previously. Hence movement in no way belongs to Him. So, some of the ancients, constrained, as it were, by the truth, decided that the first principle was immovable.”
St. Thomas Aquinas, Summa Theologica, Part I., FIRST ARTICLE [I, Q. 9, Art. 1, answer 3].
We notice here in Aquinas that he links together threads of theology proper into a tapestry that points to a supreme God. He is perfection itself. There is no composition in God thus we see Aquinas defending God’s simplicity. He cannot improve or grow in any sense as He is being itself and perfect, This God does not have potentiality as if some act was preceded by its possibility, hence Aquinas argues that immutability is necessary as God is pure act. Potentialities need to change to become actualities. This is not befitting for the Supreme God who declares, “I the Lord Change Not!!!” This is classic theology at its best. Note te Velde’s observation:
“The truth of God, in this sense, is not wholly untouched by and unrelated to how people actually think of God. What Thomas is after in his theological inquiry is not finding something previously unknown; his intention is not to provide new information
about God. To give an example: when he argues that God must be ‘immutable’, Thomas quotes a passage from the Bible in which it is said that God does not change (Mal. 3,6: Ego Deus, et non mutor). This passage is, as such, not part of the argument but, rather, the argument aims to clarify the truth hinted at in this text, by showing
that the being of God (what it is to be God) must be understood as excluding the possibility of any change. The ontological truth of the immutabilitas of God need not be part of how religious consciousness, expressing itself in this kind of biblical statement
of faith, may explain and interpret itself, since the hermeneutical selfinterpretationof (biblical) faith remains within the phenomenological objectivity of the ‘God of faith’. The divine attribute of immutabilitas, as a defi ning feature of the reality of God, does not stand on the same level as the language of faith in which the believer is intentionally directed to God; it is rather a part of the concept of God, of what it means to be God.”
Rudi te Velde, Aquinas on God
The ‘Divine Science’ of the Summa Theologiae, (Burlington, VT: Ashgate Publishing Company,) 2.
