Riyad as-Salihin: The Book of Greetings – Hadith No. 193 — Rib’i bin Hirash (May Allah be pleased with him) reported: A man of Banu ‘Amir… (Hadith No. 193)

Rib'i bin Hirash (May Allah be pleased with him) reported: A man of Banu 'Amir tribe has told us that he had asked the Prophet (ﷺ) for permission to enter when he was at home. He said: "May I enter?" the Messenger of Allah (ﷺ) said to the servant, "Go out and instruct him about the manner of seeking permission. Tell him to say: As-Salamu 'Alaikum (may peace be upon you). May I come in?" The man heard this and said: "As-Salamu 'Alaikum (may peace be upon you). May I come in?" The Prophet (ﷺ) then granted him permission and he entered..

Explanation:

Reference: Riyad as-Salihin, The Book of Greetings, Hadith No. 193