Sahih Muslim 886
صحيح مسلم#886SahihAbu Huraira reported:A person entered the mosque and said prayer while the Messenger of Allah (ﷺ) was sitting in a nook (of the mosque), and the rest of the hadith is the same as mentioned above, but with this addition:" When you get up to pray, perform the ablution completely, and then turn towards the Qibla and recite takbir (Allah o Akbar =Allah is the Most Great)
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: 4:48