Sahih Muslim Book 20, Hadith Number 4663.

Chapter : The excellence of charity in the way of Allah and its manifold reward.

It has been narrated on the authority of Abu Mas’ud al-Ansari who said A man brought a muzzled she-camel and said: It is (offered) in the way of Allah. The Messenger of Allah (may peace be upon him) said: For this you will have seven hundred she-camels on the Day of Judgment all of which will be muzzled.