Sahih al-Bukhari 6015
Sahih al-Bukhari · Book 78: Good Manners and Form (Al-Adab) · To recommend to be kind to one's neighbour
Narrates Ibn `Umar:
حَدَّثَنَا مُحَمَّدُ بْنُ مِنْهَالٍ ، حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ ، حَدَّثَنَا عُمَرُ بْنُ مُحَمَّدٍ ، عَنْ أَبِيهِ ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَا زَالَ جِبْرِيلُ يُوصِينِي بِالْجَارِ حَتَّى ظَنَنْتُ أَنَّهُ سَيُوَرِّثُهُ " .
Allah' Apostle said, Gabriel kept on recommending me about treating the neighbors in a kind and polite manner, so much so that I thought that he would order (me) to make them (my) heirs."