Sahih Muslim 152
صحيح مسلم#152SahihIt is narrated on the authority of Abu Huraira that the Prophet (ﷺ) said:Iman has over seventy branches, and modesty is a branch of Iman
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: 1:59