When the men of the place asked questions about his wife, he answered, “She is my sister.” He was afraid that, if he called her his wife, the men of the place would kill him on account of Rebekah, since she was beautiful.
David said to himself: “I shall perish some day at the hand of Saul. I have no choice but to escape to the land of the Philistines; then Saul will give up his continual search for me throughout the land of Israel, and I will be out of his reach.”