'Uthman bin 'Affan (May Allah be pleased with him) reported:
I heard Messenger of Allah ﷺ saying, "When the time for a prescribed Salat is due and a Muslim performs its Wudu' and its acts of bowing and prostration properly, this Salat will be an expiation for his past sins, so long as he does not commit major sins, and this applies for ever."

[Muslim].

وعن عثمان بن عفان رضي الله عنه قال: سمعت النبي ﷺ يقول: "ما من امرئ مسلم تحضره صلاة مكتوبة فيحسن وضوءها وخشوعها وركوعها إلا كانت كفارة لما قبلها من الذنوب مالم تؤتَ كبيرة وذلك الدهر كله" ((رواه مسلم)).