Sahih Muslim 2001
صحيح مسلم#2001SahihKa'b b. 'Ujra reported that he entered the mosque and saw Abd al-Rahman b. Umm Hakam delivering the sermon in a sitting posture. Upon this he said:Look at this wretched person; he delivers the sermon while sitting, whereas Allah said:" And when they see merchandise or sport, they break away to it and leave thee standing
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: 7:51