Narrated byAbu Ayyub, from the Prophet, peace and blessings be upon him:
Arabic (Original)
حَدَّثَنَا رَوْحٌ حَدَّثَنَا مَالِكٌ وَصَالِحٌ عَنِ ابْنِ شِهَابٍ أَنَّ عَطَاءَ بْنَ يَزِيدَ حَدَّثَهُ عَنْ أَبِي أَيُّوبَ عَنْ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَنَّهُ قَالَ لَا يَحِلُّ لِمُسْلِمٍ أَنْ يَهْجُرَ أَخَاهُ فَوْقَ ثَلَاثٍ يَلْتَقِيَانِ فَيَصُدُّ هَذَا وَيَصُدُّ هَذَا وَخَيْرُهُمَا الَّذِي يَبْدَأُ بِالسَّلَامِ.
English Translation
It was narrated from Abu Ayyub, from the Prophet, peace and blessings be upon him: that he said, "It is not permissible for a Muslim to shun his brother for more than three days, such that when they meet, this one turns away and that one turns away; and the better of the two is the one who initiates the greeting of peace."