Sunan an-Nasa'i 1561
سنن النسائي#1561SahihIt was narrated from Tha'labah bin Zahdam that:'Ali appointed Abu Mas'ud over the people, then went out on the day of 'Eid and said: 'O people, it is not part of the sunnah to pray before the imam
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih Isnaad
Al-AlbaniSahih Isnaad
Zubair Ali ZaiHasan
In-book reference: 19:6