Jami At Tirmidhi
1083
Sahih+3

Sa'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

SahihAhmad Muhammad Shakir
SahihAl-Albani