Genesis 20:11

9Then Abimelech called Abraham, and said to him, “What have you done to us? How have I sinned against you, that you have brought on me and on my kingdom a great sin? You have done deeds to me that ought not to be done!”

10Abimelech said to Abraham, “What did you see, that you have done this thing?”

11Abraham said, “Because I thought, ‘Surely the fear of God is not in this place. They will kill me for my wife’s sake.’

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

13When God caused me to wander from my father’s house, I said to her, ‘This is your kindness which you shall show to me. Everywhere that we go, say of me, “He is my brother.”’”