It was narrated from Ibn Mas'ood (رضي الله عنه) that

A man kissed a woman once, then he came to the Prophet (ﷺ) and asked him about expiation. Then the words “And perform As-Salas (Iqamatas-Salat), at the two ends of the day and in some hours of the night (i.e. the five compulsory Salat (prayers)). Verily, the good deeds remove the evil deeds (i.e. small sins).” (Hood 11:114) were revealed. The man said: O Messenger of Allah, is that only for me? He said: "It is for anyone who does that among my ummah."