مَنْ صَلَّى الْعِشَاءَ فِي جَمَاعَةٍ، فَكَأَنَّمَا قَامَ نِصْفَ اللَّيْلِ، وَمَنْ صَلَّى الصُّبْحَ فِي جَمَاعَةٍ، فَكَأَنَّمَا صَلَّى اللَّيْلَ كُلَّهُ
Translation: Whoever prays ʿIshāʾ in congregation is as though they stood in prayer for half the night; and whoever prays Ṣubḥ (Fajr) in congregation is as though they prayed the entire night.
Source: مسلم
صَلَّى means “prayed,” فِي جَمَاعَةٍ means “in congregation,” and نِصْفَ اللَّيْلِ means “half the night.” فَكَأَنَّمَا introduces a comparison: “as though.”
The merit of congregational ʿIshāʾ and Fajr is compared with prolonged night worship. The comparison encourages consistent attendance at these prayers; it does not replace the obligation of prayer or cancel other responsibilities.