Whole chapter discussed by Augustine of Hippo —
Abraham, Sarah, and Abimelech
1Now Abraham journeyed from there to the region of the Negev and settled between Kadesh and Shur. While he was staying in Gerar, 2Abraham said of his wife Sarah, “She is my sister.” So Abimelech king of Gerar had Sarah brought to him.
3One night, however, God came to Abimelech in a dream and told him, “You are as good as dead because of the woman you have taken, for she is a married woman.”
4Now Abimelech had not gone near her, so he replied, “Lord, would You destroy a nation even though it is innocent? 5Didn’t Abraham tell me, ‘She is my sister’? And she herself said, ‘He is my brother.’ I have done this in the integrity of my heart and the innocence of my hands.”
6Then God said to Abimelech in the dream, “Yes, I know that you did this with a clear conscience, and so I have kept you from sinning against Me. That is why I did not let you touch her. 7Now return the man’s wife, for he is a prophet; he will pray for you and you will live. But if you do not restore her, be aware that you will surely die—you and all who belong to you.”
8Early the next morning Abimelech got up and summoned all his servants; and when he described to them all that had happened, the men were terrified.
9Then Abimelech called Abraham and asked, “What have you done to us? How have I sinned against you, that you have brought such tremendous guilt upon me and my kingdom? You have done things to me that should not be done.” 10Abimelech also asked Abraham, “What prompted you to do such a thing?”
11Abraham replied, “I thought to myself, ‘Surely there is no fear of God in this place. They will kill me on account of my wife.’ 12Besides, she really is my sister, the daughter of my father—though not the daughter of my mother—and she became my wife. 13So when God had me journey from my father’s house, I said to Sarah, ‘This is how you can show your loyalty to me: Wherever we go, say of me, “He is my brother.”’”
14So Abimelech brought sheep and cattle, menservants and maidservants, and he gave them to Abraham and restored his wife Sarah to him. 15And Abimelech said, “Look, my land is before you. Settle wherever you please.” 16And he said to Sarah, “See, I am giving your brother a thousand pieces of silver. It is your vindication before all who are with you; you are completely cleared.”
17Then Abraham prayed to God, and God healed Abimelech and his wife and his maidservants, so that they could again bear children— 18for on account of Abraham’s wife Sarah, the LORD had completely closed all the wombs in Abimelech’s household.