Genesis 12:11-13

It came about when he came near to Egypt, that he said to Sarai his wife, “See now, I know that you are a beautiful woman; and when the Egyptians see you, they will say, ‘This is his wife’; and they will kill me, but they will let you live. Please say that you are my sister so that it may go well with me because of you, and that I may live on account of you.”