I heard the Messenger of Allah (ﷺ) saying: "One who performs 'Isha' prayer in congregation, is as if he has performed Salat for half of the night. And one who performs the Fajr prayer in congregation, is as if he has performed Salat the whole night."

[Muslim]

The narration of At-Tirmidhi says: 'Uthman bin Affan (May Allah be pleased with him) narrated that he had heard the Messenger of Allah (ﷺ) saying: "He who attends 'Isha' in congregation, is as if he has performed Salat for half of the night; and he who attends 'Isha' and Fajr prayers in congregation, is as if he has performed Salat for the whole night."