Sahih Muslim 48
Sahih Muslim · Book 1: The Book of Faith · Encouragement to honor one's neighbor and guest, and the obligation to remain silent unless one has something good to say, and the fact that all of that is part of faith
It is narrated on the authority of Abu Shuraih al-Khuzai' that the Prophet (may peace and blessings of Allah be upon him) observed:
حَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ ، وَمُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ ، جَمِيعًا عَنِ ابْنِ عُيَيْنَةَ ، - قَالَ ابْنُ نُمَيْرٍ حَدَّثَنَا سُفْيَانُ، - عَنْ عَمْرٍو ، أَنَّهُ سَمِعَ نَافِعَ بْنَ جُبَيْرٍ ، يُخْبِرُ عَنْ أَبِي شُرَيْحٍ الْخُزَاعِيِّ ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " مَنْ كَانَ يُؤْمِنُ بِاللَّهِ وَالْيَوْمِ الآخِرِ فَلْيُحْسِنْ إِلَى جَارِهِ وَمَنْ كَانَ يُؤْمِنُ بِاللَّهِ وَالْيَوْمِ الآخِرِ فَلْيُكْرِمْ ضَيْفَهُ وَمَنْ كَانَ يُؤْمِنُ بِاللَّهِ وَالْيَوْمِ الآخِرِ فَلْيَقُلْ خَيْرًا أَوْ لِيَسْكُتْ " .
He who believes in Allah and the Last Day should do good to his neighbour and he who believes in Allah and the Last Day should show hospitality to the guest and he who believes in Allah and the Last Day should either speak good or better remain silent.