Commentary for Genesis 20:14

ויתן לאברהם AND GAVE THEM UNTO ABRAHAM, so that he might he mollified and pray for him.

ויקח, He appeased him both with words and money, asking him for forgiveness and urging him to pray on his behalf. He also told him that he was welcome to stay in his country wherever he chose to settle, seeing that he would issue orders that neither he nor Sarah be molested.

So that he be mollified and pray for him. [Rashi knows this] because for taking his wife, [gifts were not necessary]. As Avimelech did not touch her, it is like he never took her. [You might ask:] Why did Avimelech need to mollify Avraham, while Pharaoh did not? The answer is: Pharaoh was completely unaware [that he had taken a married woman], because Avraham on his own craftily told Sarah (12:13): “Please say that you are my sister.” But here, they asked Avraham if she is his wife or his sister. He feared they would kill him and was compelled to say, “She is my sister.” That is why Pharaoh was smitten only with a disease for which relations are harmful, and after he returned her he no longer needed a cure. Whereas even after Avimelech had returned her, mollified Avraham and gave gifts, nonetheless it says: “Adonoy restrained every womb.” This was because Avimelech was considered a nearly deliberate sinner, since they interrogated Avraham: “Is she your wife?” As it says in Bava Kama 92a, “When a guest arrives in a city... is he asked about his wife?” [see Rashi, v. 11].