Sahih Muslim 6147

Abu Huraira reported that Moses was a modest person. He was never seen naked and Banu Isra'iI said:(He was afraid to expose his private part) because he had been suffering from scrotal hernia. He (one day) took bath in water and placed his garments upon a stone. The stone began to move on quickly. He followed that and struck it with the help of a stone (saying): O stone, my garment; O stone, my garments, O stone; until it stopped near the big gathering of Isrii'll, and this verse was revealed (pertaining to the incident):" O you who believe, be not Iike those who maligned Moses, but Allah cleared him of what they said, and he was worthy of regard with Allah" (xxxiii)