Catching up

In Genesis 21 we get caught up on our story after the strange interlude of Genesis 20.
The long-anticipated birth of Isaac finally takes place and this makes Sara very happy. But it also makes her that much more jealous of Hagar and Ishmael and she complains once again to Abraham.
So this time Abraham sends Hagar packing - sending her off into the desert alone with just some food and a skin of water. You would think he could have spared an escort for her and her infant son.
The food and water does not last long and she is soon tired and thirsty and nearing death. So God has to intervene again sending an angel to show Hagar a well and thus save her life.
So Ishmael grows up in the Desert of Paran and eventually marries an Egyptian woman.
Meanwhile, Abraham makes a peace treaty with Abimelech, the guy who supposedly tried to bed his wife in the last chapter. They settle their differences over a well and then Abraham plants a tree to commemorate the treaty.
Things seem to be going well for Abraham, but God has one more big test for him.