How authentic is the Hadith which mentions that Uthman ibn Affan, may Allah be pleased with him, issued a fatwa that whoever has intercourse but does not ejaculate should perform ablution (wudu) and wash his penis, and attributed that to the Prophet, peace and blessings be upon him, and that Ali, Zubair, Talha, and Ubayy ibn Ka’b supported that?

The hadith "Water is only from water" was acted upon in the early days of Islam, and it meant that ghusl (ritual bath) was not obligatory unless semen was discharged. This ruling was abrogated by later authentic hadiths, such as the hadith "When he sits between her four parts, and then exerts himself, ghusl becomes obligatory upon him" (Muslim added: "even if he does not discharge"), and the hadith of Aisha "When he sits between her four parts, and the circumcised part touches the circumcised part, then ghusl becomes obligatory." The Ummah is now in consensus regarding the obligation of ghusl after intercourse, even if there is no discharge, and this is the view of the majority of scholars. Some Companions who previously believed that ghusl was not obligatory except with discharge retracted their opinion after the abrogation became clear.