"The Messenger of Allah commanded us to do seven things: He commanded us to attend funerals, visit the sick, to reply (say: Yarhamuk Allah [may Allah have mercy on you]) to one who sneezes, to accept invitations, to support the oppressed, to fulfill oaths (when adjured by another) and to return greetings of Salaam." (Using translation from Nasāʾī 3778)   

أَمَرَنَا رَسُولُ اللهِ ﷺ بِسَبْعٍ أَمَرَنَا بِاتِّبَاعِ الْجَنَائِزِ وَعِيَادَةِ الْمَرِيضِ وَتَشْمِيتِ الْعَاطِسِ وَنَصْرِ الْمَظْلُومِ وَإِفْشَاءِ السَّلَامِ وَإِجَابَةِ الدَّاعِي وَإِبْرَارِ الْمُقْسِمِ أَخْرَجَاهُ فِي الصَّحِيحِ مِنْ حَدِيثِ جَرِيرٍ  

Six are the rights of a Muslim over another Muslim. It was said to him: Messenger of Allah, what are these? Thereupon he said: When you meet him, offer him greetings;when he invites you to a feast accept it. when he seeks your council give him, and when he sneezes and says:" All praise is due to Allah," you say Yarhamuk Allah (may Allah show mercy to you) ; and when he fails ill visit him; and when he dies follow his bier. (Using translation from Muslim 2162b)   

أَنَّ رَسُولَ اللهِ ﷺ قَالَ حَقُّ الْمُسْلِمِ عَلَى الْمُسْلِمِ سِتٌّ قِيلَ مَا هُنَّ يَا رَسُولَ اللهِ؟ قَالَ إِذَا لَقِيتَهُ فَسَلِّمْ عَلَيْهِ وَإِذَا دَعَاكَ فَأَجِبْهُ وَإِذَا اسْتَنْصَحَكَ فَانْصَحْ لَهُ وَإِذَا عَطَسَ فَحَمِدَ اللهَ فَشَمِّتْهُ وَإِذَا مَرِضَ فَعُدْهُ وَإِذَا مَاتَ فَاتَّبِعْ جِنَازَتَهُ  

[Machine] When the delegations came to Umar, he would ask them about their leader. "Has the sick person recovered? Does the servant answer? How is he doing? Who stands at his door? If they mentioned a particular trait, he would not remove him."  

كَانَ عُمَرُ ؓ إِذَا قَدِمَ عَلَيْهِ الْوُفُودُ سَأَلَهُمْ عَنْ أَمِيرِهِمْ أَيَعُودُ الْمَرِيضَ؟ أَيُجِيبُ الْعَبْدَ؟ كَيْفَ صَنِيعُهُ؟ مَنْ يَقُومُ عَلَى بَابِهِ؟ فَإِنْ قَالُوا لِخَصْلَةٍ مِنْهَا لَا عَزَلَهُ