The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 982
'A'isha reported that the Messenger of Allah (may peace be upon him) before his death recited often: Hallowed be Thou, and with Thy praise, I seek forgiveness from Thee and return to Thee. She reported: I said: Messenger of Allah, what are these words that I find you reciting? He said: There has been made a sign for me in my Ummah; when I saw that, I uttered them (these words of glorification for Allah), and the sign is:" When Allah's help and victory..... to the end of the surah.
Source materials are from the University of Southern California MSA site|
Hadith eBooks converted from Imaan Star