It was narrated that Kulthum Al-Khuza’i said:“A man came to the Prophet (ﷺ) and said: ‘O Messenger of Allah, how can I know, when I have done something good, that I have done well, and if I have done something bad, that I have done a bad deed?’ The Messenger of Allah (ﷺ) said: ‘If your neighbors say that you have done something good, then you have done well, and if they say that you have done something bad, then you have done something bad.’”

English translation · Sunan Ibn Majah