“Abimelech then took sheep and oxen and male and female servants, and gave them to Abraham, and restored his wife Sarah to him. Abimelech said, “Behold, my land is before you; settle wherever you please.” To Sarah he said, “Behold, I have given your brother a thousand pieces of silver; behold, it is your vindication before all who are with you, and before all men you are cleared.”” Gen. 20:14-16
Abraham is given land, 1000 pieces of silver, sheep and oxen, and servants, though God did not command Abimelech to do so, only to restore Sarah to him. Why does he do this? Unlike in Genesis 12, where the gifts were given to Abraham from Pharaoh as payment for Sarah, this time they are given after the fact when the deception is known.
The first reason is stated in v. 16: For vindication. The king of Gerar wants to fully exonerate himself by giving abundant restitution. He has just given Abraham land, so in the event Abraham decides to live in proximity, no one will be able to start the rumor mill about some event between the king and Sarah. However just as in the case of Pharaoh, it causes us to pause. Pharaoh and the king of Gerar are pagans; what do they care about Abraham’s welfare? Further, they were both deceived and would surely have the power to put Abraham to death, but they do not. Pharaoh even let Abraham keep all he had given him.
Certainly the main reason is a fear of Abraham’s God whom they did not know previously. This God had a power that was real, and it was obvious there was a hedge of protection around Abraham. God brought plagues upon both their households, and even threatened death to Abimelech. Further, God gave an additional stipulation aside from simply returning Sarah: Abraham was to pray for Abimelech so he would live (v. 7). Perhaps Abimelech added the gifts and land as a gesture of good faith in hopes Abraham would do just that.
Note that in v. 16 Abimelech refers to Abraham as Sarah’s brother, rather than her husband. We can only speculate if this was said in a sarcastic tone.