Genesis 20:1

Abraham and Abimelech

20:1 Abraham journeyed from there to the Negev region and settled between Kadesh and Shur. While he lived as a temporary resident in Gerar,

Genesis 26:1

Isaac and Abimelech

26:1 There was a famine in the land, subsequent to the earlier famine that occurred in the days of Abraham. Isaac went to Abimelech king of the Philistines at Gerar.