Surah 11. Hud, Ayah 74

According to all commentators, this means "he pleaded [lit., "argued"] with Our messengers" (who, as is evident from 29:31 , had announced to him the impending doom of Sodom and Gomorrah), and not with God Himself.

Glad-tidings: not only that he was to have a son, but that he was to be a fountain-head of prophets. So he now begins to plead at once for the sinful people to whom Lot was sent as a warner.