31 Here again there occur to me considerations which must be taken into account in a complete treatment of the subject. But the order of defence must adapt itself to the order of attack, and I reserve these outstanding questions for discussion in the next book. For the present, in regard to God Who demanded honour for God, it will suffice for me to point out that He Who was the Angel of God, when He spoke with Hagar, was God and Lord when He spoke of the same matter with Abraham; that the Man Who spoke with Abraham was also God and Lord, while the two angels, who were seen with the Lord and whom He sent to Lot, are described by the prophet as angels, and nothing more. Nor was it to Abraham only that God appeared in human guise; He appeared as Man to Jacob also. And not only did He appear, but, so we are told, He wrestled; and not only did He wrestle, but He was vanquished by His adversary. Neither the time at my disposal, nor the subject, will allow me to discuss the typical meaning of this wrestling. It was certainly God Who wrestled, for Jacob prevailed against God, and Israel saw God.
Source: On the Trinity (New Advent)