Genesis 18:1-2

"And Jehovah appeared unto him by the oaks of Mature, as he sat in the tent door in the heat of the day: and he lifted up his eyes and looked, and, lo, three men stood over against him: and when he saw them, he ran to meet them from the tent door, and bowed himself to the earth."

Genesis 18:1 is the key to Genesis 18:2. The "three men" were not men at all, but the Lord Himself accompanied by two angels. Nevertheless, they had every appearance of being men and even ate dinner with Abraham, even as our Saviour himself ate with his disciples after his resurrection from the dead (Luke 24:42,43). There is much difference of opinion as to whether or not Abraham might have recognized the Lord, due to his having seen him such a brief time previously; but it would appear that Abraham was not, at first, aware of the heavenly status of his guests. Hebrews 13:2 is apparently a reference to this very event; and there it is stated that the host entertained "angels unaware." If that is the case, we may not interpret Abraham's bowing himself to the earth as an act of worship, but as a warm friendly greeting only, after the manner and customs of the times. Scholars differ on this; and Kline thought that Abraham must have recognized the Lord at once, "Otherwise, the mention of Yahweh in Genesis 18:13 would be too abrupt."[5] However, that would appear to be the precise reason for Genesis 18:1, which makes the reader at once aware of who "the men" actually are. We cannot believe that Abraham knew it until later. "Apparently, these were: the preincarnate Word, who was with God and who was God (John 1:1), and two angels (Hebrews 13:2)."[6] Some refer to this as a "theophany."

Keil noted that, "There was a double purpose in this visit of the Lord to Abraham";[7] these were: (1) to strengthen and establish Sarah's faith that the birth of the promised son would actually occur, and (2) to announce the destruction of Sodom and Gomorrah. There were very strong reasons that underlay that second purpose, as we shall see later. This passage must not be interpreted in the loose sense that, "Yahweh appeared to Abraham by sending three men."[8]; Genesis 18:1 forbids such a view.

This whole chapter, including these first two verses, is not "from some primitive document,"[9] but it is Moses' account of a bona fide event that occurred in the life of Moses' distinguished ancestor, Abraham.