John Wesley on Genesis 18:1

This appearance of God to Abraham seems to have had in it more of freedom and familiarity, and less of grandeur and majesty, than those we have hitherto read of, and therefore more resembles that great visit which in the fulness of time the Son of God was to make to the world. He sat in the tent - door in the heat of the day - Not so much to repose himself, as to seek an opportunity of doing good, by giving entertainment to strangers.