Genesis 26:8-10

After Isaac had been there a long time, King Abimelech looked out of a window and saw Isaac hugging and kissing Rebekah. Abimelech called him in and said, “Rebekah must be your wife! Why did you say she is your sister?” “Because I thought someone would kill me,” Isaac answered. “Don't you know what you've done?” Abimelech exclaimed. “If someone had slept with her, you would have made our whole nation guilty!”