CLAIM: In Genesis 22:1, we read, “Now it came about after these things, that God tested Abraham.” Open theist John Sanders writes, “God needs to know if Abraham is the sort of person on whom God can count for collaboration toward the fulfillment of the divine project. Will he be faithful? Or must God find someone else through whom to achieve his purpose?”
RESPONSE: There are two problems with this interpretation from open theists:
First, this doesn’t fit with God’s earlier promise in Genesis 12. There, God promises that he would make an entire nation through Abraham (vv.2-3). This demonstrates that God’s plan was not contingent on Abraham’s faith.
Second, this doesn’t fit with Abraham’s own interpretation of the event. Genesis 22:5 states that Abraham believed from the beginning that Isaac would return with him (“we will worship and return to you”). Also, the author of Hebrews states that Abraham believed that God would raise Isaac from the dead.
Therefore, both God and Abraham believed that Isaac’s life was not going to be taken permanently. Instead, God was testing Abraham so that he could build his faith.
 John Sanders, The God Who Risks: A Theology of Providence (Grand Rapids: InterVarsity, 1998) 52-53.