Sahih Muslim Book 5, Hadith Number 2226.
Chapter : The likeness of one who spends (in the path of Allah) and one who withholds.
Abu Huraira reported that the Apostle of Allah (may peace be upon him) forbade (to do certain things) and then he made a mention of certain habits and said: He who gives a she-camel as a gift, for him is the reward (of the gift) both morning and evening-a reward for drinking milk in the morning and a reward for drinking milk in the evening.