Abu Rafi` Aslam (May Allah be pleased with him), the freed slave of the Messenger of Allah (ﷺ) reported:
The Messenger of Allah (ﷺ) said, "He who washes a dead body and conceals what he notices of physical defects, he will be forgiven forty times.''[Al-Hakim].
App reference: Book 7, Hadith 35
Arabic/English book reference: Book 7, Hadith 928