Jami` at-Tirmidhi 1083
جامع الترمذي#1083SahihSa'eed bin Al-Musayyab narrated from Sa'b bin Abi Waqqas:"The Messenger of Allah refused Uthman bin Ma'zun (when he asked) regarding celibacy, and if he had permitted it for him, then we would have castrated ourselves
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Bashar Awad MaaroufHasan Sahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 11:4