Genesis 18 relates that the Lord appeared to Abraham as he was sitting in his tent doorway. But “the Lord” appeared as three men. Abraham entertained them hospitably, and “He” (the Lord—but which of the three men was speaking?) predicted that when He came again later, Abraham’s wife, Sarah, would have a child. Sarah, listening nearby, laughed, since she and Abraham were both old. But the prophecy came true, for she gave birth to Isaac.
This passage fascinates Bible readers, since it refers to “the Lord” and “He” but also insists that three men, not one, visited Abraham. Was one of the three men God in the flesh while the other two were angels? Some readers have suggested that this was the Trinity—what the New Testament refers to as God the Father, the Son, and the Holy Spirit. So perhaps Abraham’s visitors were a kind of “Old Testament Trinity.”