Sahih Muslim 2755
صحيح مسلم#2755SahihAbu Haraira (Allah be pleased with him) reported Allah's Messenger (ﷺ) as saying:The most excellent fast after Ramadan is God's month. al-Muharram, and the most excellent prayer after what is prescribed is prayer during the night
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: 13:261