And Jesus answered him, The first of all the commandments [is], Hear, O Israel; The Lord our God is one Lord:
Note 4 at Mr 12:29: Jesus had repeatedly made reference to His deity (see note 1 at Joh 1:1, note 3 at Joh 5:18, note 8 at Joh 5:23, and note 23 at Joh 8:58) for which the Jews had sought to kill Him, and yet here He quoted from De 6:4 that "the LORD our God is one LORD." There are not two or three Gods, and yet Jesus claimed to be God just like God the Father. This union is a great mystery that the church has come to call the Trinity (Father, Son, and Holy Ghost - all one Lord, see note 2 at Mr 1:10). It defies human understanding but can be accepted and believed.