From Dhir [Zir] ibn Hubaish, who said: Ubay ibn Ka’b asked me: “How many [verses] are in surah Al-ahzab?” I said: Seventy-three or seventy-four verses. He said: “It used to be comparable to surah Al-baqara or longer than it. And it had the verse of stoning.” I said: Oh Abu Mundhir [i.e. Ubay], and what is the verse of stoning? He said: “If an old man and an old woman commit adultery, stone both of them irrevocably, a punishment from Allah to make an example out of them; and Allah is mighty, wise.”
‘Ali [i.e. Ibn Hazm] said: This is an authentic chain of transmission [isnad sahih], authentic as the sun, with no flaws therein.