Abu Dharr (May Allah be pleased with him) reported:
I heard the Messenger of Allah (ﷺ) saying, "When any Muslim accuses another Muslim of sin or of disbelief, the reproach rebounds upon the one who utters it, if the other person is not deserving of it."[Al- Bukhari]. (DE)
App reference (DE): Book 18, Hadith 50 (DE)
Arabic/English book reference (DE): Book 18, Hadith 1560 (DE)