It wasnarrated that Kulthum Al-Khuza'i said:
"A man came to theProphet(ﷺ) and said: 'O Messenger of Allah, how can I know, when Ihavedone something good, that I have done well, and if I have donesomething bad, that I have done a bad deed?' The Messenger of Allah(ﷺ) said: 'If your neighbors say that you have done somethinggood,then you have done well, and if they say that you have donesomethingbad, then you have done something bad.'"
English reference: Vol. 5, Book 37, Hadith 4222
Arabic reference: Book 37, Hadith 4362