Sahih Muslim 1813
صحيح مسلم#1813SahihA'raj reported that when the Messenger of Allah (ﷺ) would start the prayer, he would pronounce takbir (Allah-o-Akbar) and then say:I turn my face (up to Thee), I am the first of the believers; and when he raised his head from ruku' he said: Allah listened to him who praised Him; O our Lord, praise be to Thee; and he said: He shaped (man) and how fine is his shape? And he (the narrator) said: When he pronounced salutation he said: O Allah, forgive me my earlier (sins), to the end of the hadith; and he did not say it between the Tashahhud and salutation (as mentioned above)
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: 6:241