Kabbalah zu Bereschit 25:11

Come and behold, it is written "And Benaiah the son of Jehoida, the son of a valiant (lit. 'living') man" (II Shmuel 23:20). This means that he was righteous and illuminated his generation as the living one above illuminates the world. Thus, the well constantly looks to the living one in order to be illuminated. "And Isaac dwelt by Be'er Lachai Ro'i. "It is written, "When he took Rivkah," FOR and as he united with her, the joining of darkness and night, as it is written, "his left hand is under my head" (Shir Hashirim 2:6) And Come and behold, Isaac was in Kiryat Arba after Abraham died. What about the verse that reads, "And Isaac dwelt by Be'er Lachai Ro'i?" That with which he joined and was united in that well, to stir up love, as we said.

Rabbi Yehuda said, This is the meaning of the text indicating that it was called Abraham at one time, and is now called Isaac in his place, as it is written, "And it came to pass after the death of Abraham, that Elohim blessed his son Isaac; and Isaac dwelt by Beer Lachai Roi (lit. 'the well of living and seeing')" (Gen. 25:11). Through the knowledge of the living, the life of the world, he may know and conceive what he had not conceived in this world, as it is written, "For the earth shall be full of the knowledge of Hashem" (Isaiah 11:9). (End of Midrash Hane'elam)