But this I say: He who sows sparingly will also reap sparingly, and he who sows bountifully will also reap bountifully. So let each one give as he purpose in his heart not grudgingly or of necessity; for GOD loves a cheerful giver. And GOD is able make all grace abound toward you, that you, always having all sufficiency in all things, may have an abundance for every good work. 
2 Corinthians 9:6-8 (NIV)