Sayyidina Abu Saeed (RA) reported that Sayyidina Abu Musa (Ra) sought permission of Sayyidina Umar (RA) to enter his home, saying, “Assalamu alikum, may I come in? Umar (RA) said, this is once and he kept quiet for some time and sought permission a second time, “As-salaamu alikum, may I come in? Umar (RA) said, “This is twice, and then he kept quiet for some time. Again he said, ‘Assalaamu alikum, may I come in? Umar (Ra)‘, said, “This is thrice.’ Then he returned. Umar (RA) asked the gate-keeper what he had done. He said, ‘He has gone away.” Umar (RA) said, “Bring him to me.” When he came, Umar (RA) asked him, “What did you do?” Abu Musa said, “This is the sunnah.” Umar (RA) asked, “Is that the sunnah. By Allah, bring me an evidence and witness, or I will punish you.” Abu Sa’eed narrated futher Abu Musa came to us and we were his friends, the Ansars. He said, “O Group of Ansars, are you not those who know the ahadith of Allah’s Messenger (SAW) the best of all people? Did he not say that permission is sought three times? If you are given permission, enter otherwise turn back.” The people laughed at him, but I raised my head to him and asked, “What had befallen you in this matter? I am your partner in the punishment that you might receive.” I went to Umar (RA) and informed him of that (hadith) and he said, “I had not known this.”
[Ahmed 11029, Bukhari 6245, Muslim 2153, Abu Dawud 5170, Ibn Majah 3706]
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