Tithing is in obidience to God; plus that's how the church runs its expensses for, light bills, helping the families of the church, and if you have a full time pastor, that's his salary as well. When you are in obidiance, God will bless you even more, maybe not necessarily financially, but healthwise, peace of mind, and in all areas of your life. Nothing is impossible to God.
Tithing is important primarily for only one reason. It builds your character. But secondarily it teaches you to live within your means and help others who are in need.
Another point of view:
According to the Bible, tithing was commanded under the Mosaic Law in the nation of Israel(Deuteronomy 26:12 / 12:6 ) to support the Levites as they performed their priestly duties at the temple (Numbers 18:21-24; Deuteronomy 14:22-29). When Israel neglected to support the Levitical priesthood, they suffered spiritually, as the priests had to leave their duties to work in the fields to support themselves (Nehemiah 13:10)
As part of the Mosaic Law, 'tithing' ended with the death of Jesus(Ephesians 2:15; Colossians 2:13, 14). No longer under Law, Christians were never commanded to tithe. ( Romans 6:14) The setup for true worship completely changed from a 'physical law', with rituals and sacrifices, to 'a law in the heart', and Christians were encouraged to give whatever they could manage, PRIVATELY(Matthew 6:3-4), willingly, from the heart, to support spiritual interests in the congregation(2Corinthians 8:12; 9:7).
AND, rather than be financially supported, those taking the lead in the congregations worked at secular employment so as not to put a financial burden on their Christian brothers.(1Thessolonians 2:9).