קבלה אויף בראשית 25:20

(The word “living” is similarly used in the verse “And Benaiah the son of Jehoiada, the son of a living man” (II Sam. 23, 20), i.e. a righteous man who illumines his generation as the living Deity above illumines the universe.) So the well constantly looks to the “living one” to be illumined. Further, the statement that Isaac dwelt by Beer-lahai-roi teaches the same lesson as the statement “And Isaac was forty years old when he took Rebekah” (Gen. 25, 20), and abode with her and was united with her, symbolising in this way the union of darkness with night, as it is written: “His left hand under my head” (S. S. 2, 6). Observe now that after Abraham’s death Isaac remained in Kiriath-arba; how, then, it may be asked, can it say that he dwelt in Beer-lahai-roi? The answer is, to indicate that Isaac attached himself and held fast to that well in order to awaken the attribute of mercy, as already explained.’