Mukhtasar Muslim

It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, who states: When the Messenger of Allah, peace and blessings be upon him, said: Whoever gives charity from his pure (lawful) earnings, even if it is a single date, Allah Almighty takes it in His right hand and nurtures it as one of you nurtures his colt or young she-camel, until it (the charity of a single date) becomes like a mountain or even greater than that.

Abu Hurairah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: O people! Allah is pure (i.e., free from all defects and deficiencies) and accepts only that which is pure (i.e., lawful). And Allah has commanded the believers with the same command that He gave to the Messengers. He said: "O Messengers! Eat of the good things and do righteous deeds. Indeed, I am Knowing of what you do." And He said: "O you who believe! Eat of the good things which We have provided for you." Then he mentioned a man who undertakes a long journey, disheveled and dusty, and he raises his hands towards the sky and says: O Lord, O Lord! While his food is unlawful, his drink is unlawful, his clothing is unlawful, and he is nourished with unlawful things—so how can his supplication be accepted?