Then the LORD said, “Because the outcry against Sodom and Gomorrah is great and their sin is very grave,
20. The cry of Sodom . The Lord here begins more clearly to explain to Abraham his counsel concerning the destruction of the five cities; although he only names Sodom and Gomorrah, which were much more famous than the rest. But before he makes mention of punishment, he brings forward their iniquities, to teach Abraham that they justly deserved to be destroyed: otherwise the history would not tend to instruction.
The messengers from heaven had now despatched one part of their business, which was an errand of grace to Abraham and Sarah, and which they delivered first; but now they have before them work of another nature. Sodom is to be destroyed, and they must do it, Gen 19:13. Note, As with the Lord there is mercy, so he is the God to whom vengeance belongs.
Commenting on Genesis 18:16-22
And the Lord said,.... The Targum of Jonathan adds, to the ministering angels, the two angels that were with him in the likeness of men; or to Abraham, at least in his hearing, by which he understood that Sodom and other cities were about to be destroyed for their sins: because the cry of Sodom and Gomorrah is great; either of Lot in it, whose...