I went on an expedition with God's messenger on a camel used for drawing water which had grown weary and could scarcely go on. The Prophet came up beside me and asked what was the matter with my camel, and when I told him it had grown weary, he went behind it and urged it on. He then made supplication for it and it kept going in front of the other camels. He asked me how I found my camel and I replied that it was fine, having received the benefit of his blessing. He asked if I would sell it to him for a wuqiya, and I agreed on condition that I might ride it till we came to Medina. When God's messenger came to Medina I took the camel to him in the morning, and he gave me its price, then returned the animal to me. (Bukhari and Muslim.)