Genesis 26:15-18

For all the wells which his father's servants had digged in the days of Abraham his father, the Philistines had stopped them, and filled them with earth. And Abimelech said unto Isaac, Go from us; for thou art much mightier than we. And Isaac departed thence, and pitched his tent in the valley of Gerar, and dwelt there. And Isaac digged again the wells of water, which they had digged in the days of Abraham his father; for the Philistines had stopped them after the death of Abraham: and he called their names after the names by which his father had called them.