6. In His love for them, He called them: "Yisrael is My son, My firstborn" (Shemot 4:22), similar to the above, LIKE ZEIR ANPIN THAT IS CALLED 'FIRSTBORN.' He killed all the firstborn above and below, FROM THE OTHER SIDE, and He loosened and untied the knots and shackles, WHICH THE EGYPTIANS TIED SO THAT YISRAEL WOULD NOT BE ABLE TO LEAVE EGYPT, in order to take them out. He made them free of everything. Thus, the Holy One, blessed be He, did not wish TO TAKE THEM OUT THROUGH an angel through a seraph, but only through He Himself. Moreover, only He could distinguish BETWEEN A FIRSTBORN AND A NON-FIRSTBORN, and know everything and release the bond. It is not within the authority of any other emissary, but rather in His hand.