Full context:   Augustine, in contrast, held that the three visitors to Abraham were the three persons of the Trinity. He saw no indication that the visitors were unequal, as would be the case in Justin's reading. Then, in Genesis 19, two of the visitors were addressed by Lot in the singular: "Lot said to them, 'Not so, my lord'" (Gen. 19:18). Augustine saw that Lot could address them as one because they had a single substance despite the plurality of persons.[a]