“Al-Ṭabarānī recorded it in al-Awsaṭ, and its narrators are trustworthy, except for ʿAbd al-Malik: I have found no evidence that he heard from Abū Hurayrah. Ibn Ḥibbān said, ‘He narrated from Yazīd ibn al-Aṣamm.’”

It has another supporting report with the same meaning, narrated by ʿAmr ibn Abī Sufyān: ʿAmr ibn ʿAbd Allāh ibn Ṣafwān informed him that Kaldah ibn Ḥanbal informed him that Ṣafwān ibn Umayyah sent him to the Prophet with milk, colostrum, and small cucumbers, while the Prophet was at the upper end of the valley. He said:

“I entered upon him without offering the greeting or seeking permission, so the Prophet said:

‘Go back and say: Peace be upon you. May I enter?’”

818 — “Go back and say: Peace be upon you. May I enter?”

This occurred after Ṣafwān had embraced Islam. ʿAmr said: Umayyah ibn Ṣafwān also related this hadith to me, but he did not say that he had heard it from Kaldah. It was recorded by Aḥmad (3/414), Abū Dāwūd (5176), and al-Tirmidhī (2/118–119), who said: “A good, singular hadith.”

I say: Its chain of transmission is authentic. Abū Dāwūd (5177) also recorded, through Ribʿī, who said: A man from Banū ʿĀmir narrated to us that he sought permission to enter upon the Prophet while he was in a house, saying:

“May I enter?” The Prophet said:

“Go out to this man and teach him how to seek permission. Tell him: ‘Say: Peace be upon you. May I enter?’”

819 — “Go out to this man and teach him how to seek permission. Tell him: ‘Say: Peace be upon you. May I enter?’”

The man heard this and said: “Peace be upon you. May I enter?” The Prophet then permitted him to enter, and he entered.

I say: Its chain of transmission is also authentic. The anonymity of a Companion causes no harm; moreover, it is possible that he was Ṣafwān ibn Umayyah mentioned in the preceding hadith.