Jewish Scholars Claude Joseph Goldsmith Montefiore and Herbert Martin James Loewe,
“If man should be humble, there is a sense in which God is strangely humble too: If a pupil is ill, and the teacher goes to visit him, the other pupils go before to announce the coming of the teacher. But when God went to visit Abraham in his illness, He went first, before the angels (Gen. XVIII, 1, 2). Is there anyone more humble than He? (Tanh., Wayera, 2, f. 31b.)” [emphasis added]
Paul made the same point in Philippians 2. I agree that most people who are not Christian will see the connection of God visiting Abraham in Genesis 18 with Jesus' incarnation. But if God can take human form and see Abraham while maintaining his godly attributes - omniscience, omnipotence, and omnipresence - enthroned in heaven. If God could do that for several minutes to interact with Abraham and Sarah, He can do it for years! Say, 33 years for example - in the person of Jesus Christ. A fundamental, theological, and logical objection to the Trinity is torpedoed.
God Took Human Form (Before the Time of Jesus), part 2 of 5 | True Freethinker