Narrated `Adi bin Hatim: We came to `Umar in a delegation (during his rule). He started calling the men one by one, calling each by his name. (As he did not call me early) I said to him. "Don't you know me, O chief of the Believers?" He said, "Yes, you embraced Islam when they (i.e. your people) disbelieved; you have come (to the Truth) when they ran away; you fulfilled your promises when they broke theirs; and you recognized it (i.e. the Truth of Islam) when they denied it." On that, `Adi said, "I therefore don't care."

Narrated Sa`id bin Zaid: Allah's Messenger said, "The Kam'a (i.e. a kind of edible fungus) is like the Manna (in that it is obtained without effort) and its water is a (medicine) cure for eye trouble."

Narrated Sa`id Ibn Zaid: The Prophet said, "Al-Kam'a is like the Mann (sweet resin or gum) (in that it grows naturally without human care) and its water is a cure for the eye diseases."

Narrated Sa`id bin Zaid: I heard the Prophet saying, "Truffles are like Manna (i.e. they grow naturally without man's care) and their water heals eye diseases."