Doante

The Bible gives numerous reasons for tithing. Below are a few. The key principle is that giving reveals spiritual maturity. 
1.    Because God commands it.  Lev. 27:30.
2.    Because Jesus himself commanded it.  Matt. 23:23.
3.    Tithing demonstrates that God has first place in my heart.  Deut. 14:22-23.
4.    Tithing reminds me that everything was given to me by God!  Deut. 8:18.
5.    Tithing expresses my gratitude to God.  Deut. 16:17-18.

Each person should give what they have decided in their heart to give, not reluctantly or under compulsion, for God loves a cheerful giver.  And God is able to make all grace abound to you, that always having all sufficiency in everything, you may have an abundance for every good deed.
    - Paul the Apostle (2 Corinthians 9)