C. F. Keil and Franz Delitzsch on Genesis 26:13-17

Gen 26:13-17

Being thus blessed of Jehovah, Isaac became increasingly (הלוך, vid., Gen 8:3) greater (i.e., stronger), until he was very powerful and his wealth very great; so that the Philistines envied him, and endeavoured to do him injury by stopping up and filling with rubbish all the wells that had been dug in his father’s time; and even Abimelech requested him to depart, because he was afraid of his power. Isaac then encamped in the valley of Gerar, i.e., in the “undulating land of Gerar,” through which the torrent (Jurf) from Gerar flows from the south-east (Ritter, Erdk. 14, pp. 1084-5).