Genesis 12:11-13 (New International Version)

¹¹ As he was about to enter Egypt, he said to his wife Sarai, "I know what a beautiful woman you are. ¹² When the Egyptians see you, they will say, 'This is his wife.' Then they will kill me but will let you live. ¹³ Say you are my sister, so that I will be treated well for your sake and my life will be spared because of you."