A.W. TOZER
In this world where men forget us, change their attitude toward us as their private interests dictate, and revise their opinion of us for the slightest cause, is it not a source of wondrous strength to know that the God with whom we have to do changes not? That His attitude toward us now is the same as it was in eternity past and will be in eternity to come?
PHIL JOHNSON
God never changes. Devoid of all change—in his purposes, his promises. Because God is perfect, he cannot change for the better and he will not change for the worse—so by definition he cannot change. … God is not subject to mood swings. His attitudes are fixed.
TYNDALE BIBLE DICTIONARY
God’s immutability or constancy does not imply that he is static or immobile. He is a dynamic, living God who is constantly working (Jn 5:17). Sometimes God is described as being sorry, repenting, or changing his mind (Gn 6:6–7; 1 Sm 15:11; Jon 3:10). In their contexts, such figurative expressions show the constancy of a God who, in holiness and righteousness, always abhors sin and reacts against it.
In his grace and mercy, he forgives the penitent, and he carries out his promises without fail (Ps 110:4; Is 46:10; Jer 18:7–10; Eph 1:11). Thus, the constancy of God is significant in all human relationships with him, including petitions offered in prayer.
CHARLES HODGES
God can neither increase nor decrease. He is subject to no process of development, or of self-evolution. His knowledge and power can never be greater or less. He can never be wiser or holier, or more righteous or more merciful than He ever has been and ever must be. He is no less immutable in his plans and purposes.
We know that God is immutable in his being, his perfections, and his purposes; and we know that He is perpetually active. And, therefore, activity and immutability must be compatible.
C. H. SPURGEON
These passages are not suggesting there was a change in the character of God, only in His actions toward man based on the actions of men. It is man who changes and due to the changeless character of God, He must change His actions or dealings with man...
But God’s actions are always consistent with His character.
The immutability of God is a terror to the wicked because it means that God must always deal with men in accord with His holy character and plan...On the other hand, God’s immutability is a constant comfort to believers because it means God is faithful, always, to His promises and the principles of His Word. For this reason, God is called “the Rock” (Deut 32:4).