While we probe this (and it’s good to do that, thanks

) … I’ll post Genesis 18:1-28 New American Bible translation (in the U.S. used at Masses).
Genesis Chapter 18:1 The LORD appeared to Abraham by the terebinth of Mamre, as he sat in the entrance of his tent, while the day was growing hot.
2 Looking up, he saw three men standing nearby. When he saw them, he ran from the entrance of the tent to greet them; and bowing to the ground,
3 he said: "Sir, if I may ask you this favor, please do not go on past your servant.
4 Let some water be brought, that you may bathe your feet, and then rest yourselves under the tree.
5 Now that you have come this close to your servant, let me bring you a little food, that you may refresh yourselves; and afterward you may go on your way." “Very well,” they replied, “do as you have said.”
6 Abraham hastened into the tent and told Sarah, “Quick, three seahs of fine flour! Knead it and make rolls.”
7 He ran to the herd, picked out a tender, choice steer, and gave it to a servant, who quickly prepared it.
8 Then he got some curds and milk, as well as the steer that had been prepared, and set these before them; and he waited on them under the tree while they ate.
9 “Where is your wife Sarah?” they asked him. “There in the tent,” he replied.
10 One of them said, “I will surely return to you about this time next year, and Sarah will then have a son.” Sarah was listening at the entrance of the tent, just behind him.
11 Now Abraham and Sarah were old, advanced in years, and Sarah had stopped having her womanly periods.
12 So Sarah laughed to herself and said, “Now that I am so withered and my husband is so old, am I still to have sexual pleasure?”
13 But the LORD said to Abraham: "Why did Sarah laugh and say, ‘Shall I really bear a child, old as I am?’
14 Is anything too marvelous for the LORD to do? At the appointed time, about this time next year, I will return to you, and Sarah will have a son."
15 Because she was afraid, Sarah dissembled, saying, “I didn’t laugh.” But he said, “Yes you did.”
16 The men set out from there and looked down toward Sodom; Abraham was walking with them, to see them on their way.
17 The LORD reflected: "Shall I hide from Abraham what I am about to do,
18 now that he is to become a great and populous nation, and all the nations of the earth are to find blessing in him?
19 Indeed, I have singled him out that he may direct his sons and his posterity to keep the way of the LORD by doing what is right and just, so that the LORD may carry into effect for Abraham the promises he made about him."
20 Then the LORD said: "The outcry against Sodom and Gomorrah is so great, and their sin so grave,
21 that I must go down and see whether or not their actions fully correspond to the cry against them that comes to me. I mean to find out."
22 While the two men walked on farther toward Sodom, the LORD remained standing before Abraham.
23 Then Abraham drew nearer to him and said: "Will you sweep away the innocent with the guilty?
24 Suppose there were fifty innocent people in the city; would you wipe out the place, rather than spare it for the sake of the fifty innocent people within it?
25 Far be it from you to do such a thing, to make the innocent die with the guilty, so that the innocent and the guilty would be treated alike! Should not the judge of all the world act with justice?"
26 The LORD replied, “If I find fifty innocent people in the city of Sodom, I will spare the whole place for their sake.”
27 Abraham spoke up again: "See how I am presuming to speak to my Lord, though I am but dust and ashes!
28 What if there are five less than fifty innocent people? Will you destroy the whole city because of those five?" “I will not destroy it,” he answered, “if I find forty-five there.”
Definitely the LORD is a character in this … not just three men, though they appeared that way, and behaved that way in speaking, walking, being visible, taking hospitality in eating and drinking. “Angels” aren’t specifically mentioned until later, when, in Sodom supernatural powers blind the mob of rapists who clamored at Lot’s door. Then “angels” speak -
Gen 19:12.
Verse 22 has “two men” walking on toward Sodom while
the LORD remains behind talking with Abraham
< - who recognizes him as the LORD - and begins to try to save Sodom (due to the proposition that there may be innocent people there not deserving of destruction equally). The LORD agrees to every new proposition Abraham makes in the case of mercy. Abraham negotiates the number down to ten … then goes no further.
As it turned out just four escape Sodom’s fate by fleeing (reluctantly!) before the doom. So did Abraham’s intercessory pleadings stop too soon?

The LORD did make a distinction between the four and the city anyway. And saved the town of Zoar later at Lot’s request too!
Singular and plural as regards the Lord and the “three men”.

Abraham in verses 1 and 2 sees THEM … but in verse 3 begins his discourse with the singular “Sir …” and immediately presents himself as their servant.
A hint about the mystery of the trinity? Just before Abraham is introduced, in Chapter 11, the LORD comes down to view the “tower to the sky men are building”. And refers to (Himself ?) as “us” < **Genesis 11:7. ** One LORD. Yet a mysterious “us”.
I await further instruction on the matter (from the Church) but when reading the passages I do think of the Trinity. Without the need to really MAKE the other two figures in Ch. 18 or the “us” in Chapter 11 the other members of the Trinity.
There are some pretty knowledgable folks around here. Some good insights may be headed our way.
