al-Aḥādīth al-Mukhtārah (1/407), through several routes from al-Ḥasan, from ʿUtayy ibn Ḍamrah al-Saʿdī, from Ubayy ibn Kaʿb, who heard a man say: “O, [the clan] of so-and-so!” Ubayy said to him, “Bite your father’s penis,” without using euphemism. The man said to him, “O Abū al-Mundhir, you were not one to use obscene language.” He replied, “I heard the Messenger of Allah, may Allah’s peace and blessings be upon him, say it,” and then mentioned the hadith.

I say: The narrators in this chain of transmission are trustworthy, so it is authentic if al-Ḥasan heard it from ʿUtayy ibn Ḍamrah. However, he practised tadlīs and transmitted it using the ambiguous “from” formula. Ibn al-Sunnī (427) also narrated it through Saʿīd ibn Bashīr, from Qatādah, from al-Ḥasan, from Makḥūl, from ʿUjr ibn Midrāʿ al-Tamīmī, who said: “O Tamīm!”—and he was from Banū Tamīm, and was with Ubayy ibn Kaʿb—so Ubayy said: “May Allah cause you to bite your father’s penis.” The hadith is similar in wording.

This differs from the first chain, and that one is sounder, since this one contains Saʿīd ibn Bashīr, who is weak. Perhaps he erred in it; otherwise, al-Ḥasan would have had two chains of transmission for it from Ubayy.

I have found another chain of transmission for the hadith from Ubayy. ʿAbd Allah ibn Aḥmad said (5/133): “Muḥammad ibn ʿAmr ibn al-ʿAbbās al-Bāhilī narrated to us: Sufyān narrated to us, from ʿĀṣim, from Abū ʿUthmān, from Ubayy: A man raised a tribal rallying cry, so Ubayy told him to bite his father’s penis. They said, ‘You were not one to use obscene language.’ He replied, ‘We were commanded to do so.’”

Al-Ḍiyāʾ also narrated it through ʿAbd Allah in al-Mukhtārah (1/405).

I say: This is an authentic chain of transmission. All its narrators are trustworthy and are narrators of al-Bukhārī and Muslim, apart from Muḥammad ibn ʿAmr, who is trustworthy, as Abū Dāwūd and others stated. ʿĀṣim is Ibn Sulaymān al-Aḥwal, and Sufyān is Ibn ʿUyaynah.

Note: Ubayy is not identified by lineage in al-Adab al-Mufrad, and this was the reason for an oversight