Genesis 20:9-12

9Abimelech summoned Abraham and said to him, “What have you done to us? What sin did I commit against you that would cause you to bring such great guilt on me and my kingdom? You have done things to me that should not be done!”

10Then Abimelech asked Abraham, “What prompted you to do this thing?”

11Abraham replied, “Because I thought, ‘Surely no one fears God in this place. They will kill me because of my wife.’

12What’s more, she is indeed my sister, my father’s daughter, but not my mother’s daughter. She became my wife.