Does God change or not?

In today's sermon I asserted that while human nature was not changed by the Flood, that God changed, determining to respond to ongoing human wickedness with mercy instead of vengeance. I argued that this change could be seen in God's commitment to never again destroy the world with a flood: "Whenever I bring clouds over the earth and the rainbow appears in the clouds, I will remember my covenant between me and you and all living creatures of every kind. Never again will the waters become a flood to destroy all life." (Genesis 9:14-15 NIV).

This may have raised some red flags for some of you. In question 4 of the Westminster Shorter Confession we are told that "God is a Spirit, infinite, eternal, and unchangeable, in his being..." Throughout Scripture there are verses that speak of God being constant: "He who is the Glory of Israel does not lie or change his mind; for he is not a human being, that he should change his mind." (1 Samuel 15:29).

And yet an honest reading of Scripture must acknowledge the numerous occasions where God diverts from the course of action God had promised. Here is just a few of many examples given in the article "Does God change his mind?":

• Ex 32:14—Because of Moses’ intercessory prayer after the 'gold calf' incident, “the Lord changed his mind about the disaster he planned to bring on this people.”
• 2 Kings 10:1-6—King Hezekiah was told through an inspired prophet that he would not recover from sickness. But after Hezekiah pleaded with God, the Lord told him “I will add fifteen years to your life.”
• Jonah 3:10—God “changed his mind” about the destruction he planned to carry out on Nineveh.

It can become a game of mental gymnastics to try to reconcile these diverging characterisations of God and God's nature.

Maybe one way of understanding them is to realize that even if God's character fundamentally does not change, God's response to specific situations can alter. Maybe a complentary way of understanding these conflicts is to realise that the revelation of God's character is progressive in Scripture: God's nature is more clearly defined over time. Maybe the final way of making sense of these contradictions it to realise that certain Scriptures must ultimately exist in tension, and that when it comes to God much mystery remains.