Blessings to all,
Welcome again, I am Jerry, this portion of our study covers:

GOD REAFFIRMS HIS PROMISE part 2

Once the meal is over, the Lord fully reveals Himself, in a conversation He conducts with Sarah through Abraham while she remains hidden and listening in the tent. First, the Lord asks where Sarah is and then reveals to her what He had said to Abraham in the previous chapter: by this time a year from now she will have a son.

Sarah's response is much the same as Abraham's in the previous chapter: she laughs to herself. Not only was she around 90 years old, we're told that the "way of women" had ceased for her. The phrasing here might suggest the idea of menopause: Sarah is literally "beyond" a woman's normal ability to conceive. She describes herself as worn out and her husband as old. 

She cannot imagine having the "pleasure" of a new birth in their season of life. The Lord knows both that Sarah laughed and what she thought about His revelation. He asks Abraham why she laughed.

"Is anything too hard for the LORD?" 

Then He repeats the promise of a son at the appointed time. Sarah, likely realizing now that this is God, is afraid. She lies and says that she did not laugh. The Lord corrects her once more, but He does not punish her. In another instance of divine humor, He has already named her child Isaac, which means laughter.

The three men then set out on their journey, walking from Abraham's home near Hebron toward the city of Sodom. Abraham walks with them for a time, until they arrive at a high vantage point from which they can look across and see Sodom. From there, the Lord reveals to Abraham His plan regarding the grave sins of Sodom and Gomorrah. 

The implication is that God will bring judgment on those people if their sins were as wicked as He had heard. This, of course, is a figure of speech, since God already knows exactly how sinful these cities are. The reason for this human perspective is revealed in the conversation with Abraham, as Abraham tries to specify just "how wicked" these cities must be to earn God's wrath.

As the two angels walk on toward the city, Abraham begins a kind of negotiation with the Lord. His nephew Lot and his family live in Sodom. Abraham seems to be concerned for them. 

He boldly challenges the Lord: 

Will you sweep away the righteous with the wicked?

Abraham insists that such an action would not be consistent with the Lord's character. The Lord is patient with Abraham as he begins to ask for assurances.

Will you destroy the city if you find 50 righteous people there?

The Lord agrees that He will not. Abraham keeps asking though, lowering the number at which the Lord would willingly destroy righteous people to judge the wicked.

45? 40? 30? 20?

Finally, Abraham asks, with a request that the Lord not be angry, if He would spare the city for the sake of 10 righteous people. Once more, the Lord agrees that He would do so if He finds that many. With that, the Lord heads toward the city, and Abraham walks back home.