Sunan of Abu Dawood Book 43, Hadith 5180

حَدَّثَنَا أَحْمَدُ بْنُ عَبْدَةَ، أَخْبَرَنَا سُفْيَانُ، عَنْ يَزِيدَ بْنِ خُصَيْفَةَ، عَنْ بُسْرِ بْنِ سَعِيدٍ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ، قَالَ كُنْتُ جَالِسًا فِي مَجْلِسٍ مِنْ مَجَالِسِ الأَنْصَارِ فَجَاءَ أَبُو مُوسَى فَزِعًا فَقُلْنَا لَهُ مَا أَفْزَعَكَ قَالَ أَمَرَنِي عُمَرُ أَنْ آتِيَهُ فَأَتَيْتُهُ فَاسْتَأْذَنْتُ ثَلاَثًا فَلَمْ يُؤْذَنْ لِي فَرَجَعْتُ فَقَالَ مَا مَنَعَكَ أَنْ تَأْتِيَنِي قُلْتُ قَدْ جِئْتُ فَاسْتَأْذَنْتُ ثَلاَثًا فَلَمْ يُؤْذَنْ لِي وَقَدْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ إِذَا اسْتَأْذَنَ أَحَدُكُمْ ثَلاَثًا فَلَمْ يُؤْذَنْ لَهُ فَلْيَرْجِعْ ‏"‏ ‏.‏ قَالَ لَتَأْتِيَنِّي عَلَى هَذَا بِالْبَيِّنَةِ قَالَ فَقَالَ أَبُو سَعِيدٍ لاَ يَقُومُ مَعَكَ إِلاَّ أَصْغَرُ الْقَوْمِ ‏.‏ قَالَ فَقَامَ أَبُو سَعِيدٍ مَعَهُ فَشَهِدَ لَهُ ‏.‏

Abu Sa'id al-Khudri said:I was sitting in one of the meeting of the Ansar. Abu Musa came terrified. We asked him; what makes you terrified? He replied: ‘Umar sent for me; so I went to him and asked his permission three times, but he did not permit me (to enter), so I came back. He asked; what has prevented you from coming to me? I replied: I came and asked permission three times, but it was not granted to me (so I returned). The Messenger of Allah (May peace be upon him) has said: When one of you asks permission three times and it is not granted to him, he should go away. He (‘Umar') said; establish the proof of it. So Abu Sa'id said: the youngest of the people will accompany you. So Abu Sa'id got up with him and testified