It wasnarrated that Ibn Ma'qil said:
"I entered with my father upon'Abdullah, and I heard him say: 'The messenger of Allah (ﷺ)said:"Regret is repentance." My father said: 'Did you hear theProphet(ﷺ) say: "Regret is repentance?" He said: 'Yes.'" (FR)
English reference (FR): Vol. 5, Book 37, Hadith 4252 (FR)
Arabic reference (FR): Book 37, Hadith 4393 (FR)