Sahih Muslim 6917
صحيح مسلم#6917SahihThis hadith has been transmitted on the authority of Ibn Abi Laili but with this addition:" Ali said: Ever since I heard this (supplication) from Allah's Apostle (ﷺ), I never abandoned it. It was said to him, Not even in the night of Siffin (battle of Siffin)? He sad: Yes, not even in the night of Siffin
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 48:110