God promises Abram that he will be the father of a multitude of nations, and thus names him Abraham, which is a name that bears similarity to other words that mean father of a multitude. The covenant comes with a command to be circumcised. God promises that Abraham will have a child from Sarah, who laughs when she hears it, because she had been infertile and now she was much older.
Abraham shows the Lord tremendous hospitality, and God tells him that He will destroy Sodom and Gomorrah. Abraham pleads with God to spare the righteous, knowing that Lot and his family are there. God declares that He will not destroy the city if even 10 righteous people are there.
Angels of God come to Sodom and Gomorrah and Lot invites them to come to his home to keep them from the people of the city, as the people there were notorious for their wicked treatment of men, a sentiment that you can also find in verses Isaiah 1:10ff, Jeremiah 23:14, Ezekiel 16:49-50, and Jude 1:6-7.
The people in the town threaten to rape the angels of God. Lot, in desperation, offers the men his daughters to protect the angels, but the angels protect Lot. In the morning, the angels tell Lot to take his family and leave the city so that they may destroy it, and Lot begs that he be allowed to settle in a nearby city, which he is allowed to do. Lot is pressed to leave but his wife looks back and is turned to a pillar of salt.