Hadith 17:370
Abu al-Ahwas narrated to us, from Mansur, from Rib'i, who said: A man from Banu 'Amir narrated to me: He sought permission to enter upon the Prophet, may Allah bless him and grant him peace, while he was in a house, and said, "May I enter?" The Prophet, may Allah bless him and grant him peace, said to his servant, "Go out to this man and teach him how to seek permission, and say to him: Say, 'Peace be upon you, may I enter?'" The man heard him, so he said, "Peace be upon you, may I enter?" The Prophet, may Allah bless him and grant him peace, gave him permission, and he entered.
حدثنا أبو الأحوص عن منصور عن ربعي قال حدثني رجل من بني عامر استأذن علي النبي صلى الله عليه وسلم وهو في بيت فقال أألج فقال النبي صلى الله عليه وسلم لخادمه أخرج إلى هذا فعلمه الاستئذان وقل له قل السلام عليكم أأدخل فسمعه الرجل فقال السلام عليكم أأدخل فأذن له النبي صلى الله عليه وسلم فدخل