It is narrated from Hazrat Aisha (may Allah be pleased with her) that in the last part of his life, the Prophet (peace and blessings be upon him) used to frequently say: "Subhan Allah wa bihamdihi, astaghfirullah wa atubu ilayk." Once I asked, "O Messenger of Allah! I hear you reciting these words frequently, what is the reason for this?" The Prophet (peace and blessings be upon him) replied, "My Lord had informed me that I would see a sign in my Ummah, and He commanded me that when I see that sign, I should glorify Allah with His praise and seek His forgiveness, for He is Most Accepting of repentance. And I have seen that sign." Then the Prophet (peace and blessings be upon him) recited the entire Surah: "Iza ja'a nasrullahi wal fath."