(35) باب قَوْلِ اللَّهِ تَعَالَى {يُرِيدُونَ أَنْ يُبَدِّلُوا كَلاَمَ اللَّهِ}
Narrated Abu Huraira:
I heard the Prophet (ﷺ) saying, "If somebody commits a sin and then says, 'O my Lord! I have sinned, please forgive me!' and his Lord says, 'My slave has known that he has a Lord who forgives sins and punishes for it, I therefore have forgiven my slave (his sins).' Then he remains without committing any sin for a while and then again commits another sin and says, 'O my Lord, I have committed another sin, please forgive me,' and Allah says, 'My slave has known that he has a Lord who forgives sins and punishes for it, I therefore have forgiven my slave (his sin). Then he remains without Committing any another sin for a while and then commits another sin (for the third time) and says, 'O my Lord, I have committed another sin, please forgive me,' and Allah says, 'My slave has known that he has a Lord Who forgives sins and punishes for it I therefore have forgiven My slave (his sin), he can do whatever he likes."
Reference: Sahih al-Bukhari 7507
In-book reference: Book 97, Hadith 132
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 9, Book 93, Hadith 598