Hadith 3318
Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said: "When any one of you gives charity from pure earnings—even if it is a single date—Allah Almighty accepts only pure earnings. Allah Almighty takes it in His Hand of Power and begins to nurture it, just as one of you raises his young animal, until in the Hand of Allah Almighty, it (the single date) becomes like a mountain."