صحيح البخاري

Narrated Al-Bara' bin `Azib:

The Prophet (ﷺ) forbade us to use seven things: He forbade using gold rings, silk, Istabraq, Dibaj, red Mayathir, Al-Qassiy, and silver utensils. He ordered us to do seven other things. To pay a visit to the sick; to follow funeral processions; to say, "May Allah be merciful to you" to a sneezer if he says "Praise be to Allah"; to return greetings, to accept invitations; to help others to fulfil their oaths and to help the oppressed ones.