The Book of Zakat (Kitab Al-Zakat)
Muslim :: Book 5 : Hadith 2179
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying that Allah said to him:" Spend, I will bestow upon you." And the Messenger of Allah (may peace be upon him) said: The right hand of Allah is full and spending (the riches) liberally during day and night will not diminish (the resources of Allah). Don't you see what (an enormous amount of resources) He has spent since He created the heaven and the earth, and what is in His right hand has not decreased? His Throne is upon the water. And in His other hand is death, and He elevates and degrades (whom He likes).