‏النكاح : Hadeeth No:3239 Sa'id b. al Musayyib heard Sa'd b. Abi Waqqas (Allaah be pleased with him) saying that Uthman b. Maz'un decided to live in celibacy, but Allaah's Messenger (sallAllaahu alayhi wa sallam) forbade him to do so, and if he had permitted him, we would have got ourselves castrated....

‏الزهد والرقائق‏ : Hadeeth No:7062 Mutarrif reported on the authority of his father: I went to Allaah's Prophet (sallAllaahu alayhi wa sallam). The rest of the hadith is the same....