Genesis 20:8-13

8So Abimelech rose early in the morning and called all his servants and told them all these things. And the men were very much afraid.

9Then Abimelech called Abraham and said to him, "What have you done to us? And how have I sinned against you, that you have brought on me and my kingdom a great sin? You have done to me things that ought not to be done."

10And Abimelech said to Abraham, "What did you see, that you did this thing?"

11Abraham said, "I did it because I thought, 'There is no fear of God at all in this place, and they will kill me because of my wife.'

12Besides, she is indeed my sister, the daughter of my father though not the daughter of my mother, and she became my wife.

13And when God caused me to wander from my father's house, I said to her, 'This is the kindness you must do me: at every place to which we come, say of me, "He is my brother."'"