When does the imam fall under the meaning of the hadith (If one of you leads the prayer, he should shorten it, for there is an old man and a sick person behind him . . . )?

The Shaykh: And he lengthens the prayer for us! So the Messenger sent for Mu'adh, and he said to him: , three times , and perhaps he mentioned other things , so if an imam leads the people in the 'Isha' prayer and recites surahs of about this length, and one of the praying people says: "My brother, you have lengthened it for us," and he no longer prays behind him, this hadith does not include this imam, but it includes the imam who contradicts the Sunnah, whether in this example or in other examples, this is the meaning of the hadith: .