Genesis 26:7-9

7But when the men of that place asked about his wife, he said, “She is my sister.” For he was afraid to say, “She is my wife,” since he thought to himself, “The men of this place will kill me on account of Rebekah, because she is so beautiful.”

8When Isaac had been there a long time, Abimelech king of the Philistines looked down from the window and was surprised to see Isaac caressing his wife Rebekah. 9Abimelech sent for Isaac and said, “So she is really your wife! How could you say, ‘She is my sister’?”

Isaac replied, “Because I thought I might die on account of her.”