The Messenger of Allah (may Allah bless him and grant him peace) said:
“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.”
[Sahih Muslim]
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