Malachi 3:10 (NIV)
Bring the whole tithe into the storehouse, that there may be food in my house. Test me in this,” says the Lord Almighty, “and see if I will not throw open the floodgates of heaven and pour out so much blessing that there will not be room enough to store it.
II Corinthians 9:6-7 (ASV)
But this I say, he that soweth sparingly shall reap also sparingly; and he that soweth bountifully shall reap also bountifully. Let each man do according as he hath purposed in his heart: not grudgingly, or of necessity: for God loveth a cheerful giver.