Sayyidah Asma' bint Abi Bakr (may Allah be pleased with her) said: the Messenger of Allah (peace and blessings be upon him) said to me: "Spend, and give freely like this and like this. Do not count, lest Allah count when giving to you, and do not hoard, lest Allah withhold from you."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7813