Vayishlach

(23) That same night he arose, and taking his two wives, his two maidservants, and his eleven children, he crossed the ford of the Jabbok. (24) After taking them across the stream, he sent across all his possessions. (25) Jacob was left alone. And a man wrestled with him until the break of dawn. (26) When he saw that he had not prevailed against him, he wrenched Jacob’s hip at its socket, so that the socket of his hip was strained as he wrestled with him. (27) Then he said, “Let me go, for dawn is breaking.” But he answered, “I will not let you go, unless you bless me.” (28) He said to him, “What is your name?” He replied, “Jacob.” (29) He said, “Your name shall no longer be Jacob, but Israel, for you have striven with beings divine and human, and have prevailed.” (30) Jacob asked, “Pray tell me your name.” But he said, “You must not ask my name!” And he took leave of him there. (31) So Jacob named the place Peniel, meaning, “I have seen a divine being face to face, yet my life has been preserved.”

Rabbi Chama bar Chanina said, "He was the ministering angel of Esav. And that is [what he meant] when he said to him, 'For this have I seen your face as I saw the face of God and you have accepted me' (Genesis 33:10). There is a parable about an athlete that got up and wrestled with the son of the king. He lifted his eyes and he saw that the king was standing behind him and [so] he fell to the ground in front of [the son]. This is what [is meant by that which] is written, 'and he saw that he could not overcome him.'" Rabbi Levi said, "'And he saw' the Divine Presence 'and he could not overcome him.'" Said Rabbi Berachia, "We do not know who won, whether it was the angel or whether it was Yakov.

(3) What did the Holy One, blessed be He, do? He sent an angel to him to deliver him, and to save him from the hand of Esau; and he appeared unto him like a man...

Again the angel said to him: "Let me go" (Gen. 32:26). Jacob answered him: I will not let you go until you have blessed me; and he blessed him, as it is said, "And he blessed him there" (Gen. 32:29). Again he said to him: "Let me go" (Gen. 32:26). He answered him: I will not let you go until you tell me what your name is. And (the angel) called his name Israel like his own name, for his own name was called Israel.