Abu Hurairah رضي الله تعالى عنهreported Allah’s Messenger صلى الله عليه وسلم as saying,
“Six are the rights of a Muslim over another Muslim.
It was said to him: Allah’s Messenger, 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.”