Genesis 26:1, 8

There was a famine in the land, besides the first famine that was in the days of Abraham. And Isaac went to Abimelech king of the Philistines, in Gerar.

Now it came to pass, when he had been there a long time, that Abimelech king of the Philistines looked through a window, and saw, and there was Isaac, showing endearment to Rebekah his wife.