(48) باب فِي فَضْلِ صَلاَةِ الْجَمَاعَةِ
'Uthman b. 'Affan reported the Messenger of Allah (may peace be him) as saying; if anyone says the night prayer in congregation, he is like one who keeps vigil (in prayer) till midnight; and he who says both the night and dawn prayer in congregation is like one who keeps vigil (in prayer) the whole night.
Reference: Sunan Abi Dawud 555
In-book reference: Book 2, Hadith 165
English translation: Book 2, Hadith 555