Genesis 20:2, 5, 12-13

Now Abraham said of Sarah his wife, “She is my sister.” And Abimelech king of Gerar sent and took Sarah.

Did he not say to me, ‘She is my sister’? And she, even she herself said, ‘He is my brother.’ In the integrity of my heart and innocence of my hands I have done this.”

But indeed she is truly my sister. She is the daughter of my father, but not the daughter of my mother; and she became my wife. And it came to pass, when God caused me to wander from my father’s house, that I said to her, ‘This is your kindness that you should do for me: in every place, wherever we go, say of me, “He is my brother.” ’ ”