Genesis 21, Why did God give Abraham permission to put away Hagar and Ishmael?

Question: Why did God give Abraham permission to put away Hagar and Ishmael? Whenever I read the story of Hagar and Ishmael, I feel sorry for her because it appears she was wronged. Answer: Hagar was wronged, but that began when Abraham & Sarah tried to fulfill God's promise on their own. Our unbelief has long-lasting impact and it hurts people. There is also a spiritual picture here, which Paul explains in Galatians 4:21-31: the flesh and the Spirit cannot coexist. And finally, through this Hagar and Ishmael get to have their own experience with God, learning to trust Him to provide. -PJ