Gen 26:6-11

6So Isaac settled in Gerar.7When the men of the place asked him about his wife, he said, “She is my sister”; for he was afraid to say, “My wife,” thinking, “or else the men of the place might kill me for the sake of Rebekah, because she is attractive in appearance.”8When Isaac had been there a long time, King Abimelech of the Philistines looked out of a window and saw him fondling his wife Rebekah.9So Abimelech called for Isaac, and said, “So she is your wife! Why then did you say, ‘She is my sister’?” Isaac said to him, “Because I thought I might die because of her.”10Abimelech said, “What is this you have done to us? One of the people might easily have lain with your wife, and you would have brought guilt upon us.”11So Abimelech warned all the people, saying, “Whoever touches this man or his wife shall be put to death.”