My lord: The Hebrew text uses ’adonay, which always refers to God. In Hebrew tradition, people said this word when they saw the letters of God's holy name ("Yahweh") in the text. The text here might use ’adonay instead of the more common ’adoni to show this was the angel of the Lord, meaning the Lord himself (see study note on 16:7). We do not know if Abraham knew who his visitors were at first. But by the end of the story, he knew he had been talking with God.