Abu Huraira reported that Abu'l-Qasim (one of the names of Allah's Messenger [may peace be upon him]) said
He who accused his slave of adultery, punishment would be imposed upon him on the Day of Resurrection, except in case the accusation was as he had said.
This hadith has been narrated on the authority of Ibn Ghazwan (and the words are)
" I heard Abu'l-Qasim (ﷺ) as the Prophet of repentance."