"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 وَإِجَابَةِ الدَّاعِي وَنَصْرِ الْمَظْلُومِ وَإِبْرَارِ الْقَسَمِ وَرَدِّ السَّلَامِ»