Ibn ‘Abbas said that staying for a short time and making little noise when visiting an invalid is part of the sunna. He reported God’s messenger as saying, when their clamour and disagreement became excessive, ‘‘Get up and leave me.”(This was during the Prophet's last illness, the disagreement taking place regarding the advisability of the Prophet giving them further written instructions.)
‘Umar b. al-Khattab reported God’s messenger as saying, “When you visit an invalid tell him to make supplication for you, for his supplication is like that of the angels.”
Anas reported God's messenger as saying, “A visit should last as long as the time between the two milkings of a she-camel.”(The reference is to the practice of drawing some milk from the camel, then leaving her for a little for her young to suck milk. When she then let her milk flow copiously she was milked again.) In the version of Sa'id b. al-Musayyib in mursal form it says, “The best type of sick visit is when one gets up and departs soon.”(While this is more explicit to one who is not familiar with the milking of camels, the meaning is the same as in the form given by Anas.)