Tithes

The practice of giving a tenth of one's income or property as an offering to God.
(from Nelson's Illustrated Bible Dictionary, Copyright (c)1986, Thomas Nelson Publishers)

Mark 12:41-44
Jesus sat down opposite the place where the offerings were put and watched the crowd putting their money into the temple treasury. Many rich people threw in large amounts. 42 But a poor widow came and put in two very small copper coins, worth only a fraction of a penny. 43 Calling his disciples to him, Jesus said, "I tell you the truth, this poor widow has put more into the treasury than all the others. 44 They all gave out of their wealth; but she, out of her poverty, put in everything-all she had to live on."
(NIV)

1 Cor 16:2
On the first day of every week, each one of you should set aside a sum of money in keeping with his income, saving it up, so that when I come no collections will have to be made
(NIV)

2 Cor 8:12
For if there is first a willing mind, it is accepted according to what one has, and not according to what he does not have.
NKJV

2 Cor 9:6-7
Remember this: Whoever sows sparingly will also reap sparingly, and whoever sows generously will also reap generously. 7 Each man should give what he has decided in his heart to give, not reluctantly or under compulsion, for God loves a cheerful giver.
NIV

Mal 3:10
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 you will not have room enough for it.
(NIV)

Phil 4:15-18
Moreover, as you Philippians know, in the early days of your acquaintance with the gospel, when I set out from Macedonia, not one church shared with me in the matter of giving and receiving, except you only; ........... They are a fragrant offering, an acceptable sacrifice, pleasing to God.
NIV

Gal 6:7-8
Do not be deceived: God cannot be mocked. A man reaps what he sows. 8 The one who sows to please his sinful nature, from that nature will reap destruction; the one who sows to please the Spirit, from the Spirit will reap eternal life.
NIV