Narrated from Abu Hurayrah that the Messenger of Allah (ﷺ) said:

“The rights of one Muslim over another are six.” It was said: What are they, O Messenger of Allaah? He said: “If you meet him, greet him with salaam; if he invites you, accept the invitation; if he asks for advice, give him sincere advice; if he sneezes and praises Allaah, say Yarhamuk Allaah (may Allaah have mercy on you); if he falls sick, visit him; and if he dies, attend his funeral.”

Sahih Muslim 2162