Anas told that when a man had asked the Prophet for enough sheep to fill the valley between two mountains and had been given them, he went to his people and said, "Accept Islam, my people, for I swear by God that Muhammad gives gifts to such an extent that there is no fear of poverty[*]."
*The translation depends on whether the verb is read as active or passive. The translation above takes it in the passive sense. If it is active, it means that the Prophet does not fear poverty.
Muslim transmitted it.