This is not an issue of salvation. If you are saved, tithing or not tithing won't change that. But it is a way of honoring GOD's will. Yes, we are under the New Covenant, but GOD gave us ALL of His Word, not just half. Jesus didn't nullify the Law, He just fulfilled it. GOD is the same yesterday, today, and forever. Matthew 5:17-19; Malachi 3:6; II Timothy 3:16-17
GOD set up tithe, so that the church (or temple in the OT) could function: so that the ministers could do full-time ministry as their occupation and do thier calling to serve the church body - teach, train, guide, protect, support and encourage each person to be a minister and representative of Christ out in the world. It was never about social clubs, financial profits, or personal projects. Giving tithes and offerings is something we do out of our own free will and individual conviction, in order to fulfill GOD's purpose of providing for those who study GOD's Word and pray 8+ hours a day so that they can shepherd those in the church. This is different from "giving" which is to give back materially or monitarily out of what we've been given - to those in need. Leviticus 27:30-32; Deuteronomy 12:3-8; Numbers 18:21; I Timothy 5:17-18; I John 3:16-22; Ephesians 4:11-16
I think nb_christseeker said it very well. Here are the Scripture verses he was talking about:
God said in the Old Covenant, "Will a man rob God? Yet you are robbing Me! But you say, 'How have we robbed You?' In tithes and offerings. "You are cursed with a curse, for you are robbing Me, the whole nation of you! " Bring the whole tithe into the storehouse, so that there may be food in My house, and test Me now in this," says the LORD of hosts, "if I will not open for you the windows of heaven and pour out for you a blessing until it overflows." Malachi 3:8-11
But God is speaking His heart here - not just law.
Jesus, talking about the pharisees said, "Woe to you, teachers of the law and Pharisees, you hypocrites! You give a tithe of your spices: mint, dill and cummin. But you have neglected the more important matters of the law: justice, mercy and faithfulness. You should have practiced the latter, without neglecting the former. You blind guides! You strain out a gnat but swallow a camel." Matthew 23:23-24 See also Luke 11:42-43
Sure Jesus was talking to people under the law - but look also what Jesus taught us:
"For I tell you that unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven." Matthew 5:20
The New Covenant is entered by grace and faith but sustained through being led by the Spirit, to be used to DO good works. Free from obligation to be passionate about GOD and the things of GOD. James 1:22; 3:26
GOD certainly doesn't need our money. He gives us all we have to begin with. What He does require is our obedience. GOD doesn't command us to give tithes and offerings, but as Christians we should strive to be at the spiritual place where we would want to. Tithes and offering is a an attitude of appreciation and faith as well as being a principle made throughout the entire Bible. We should not be looking for ways to get out of tithing, nor feel like tithing is a requirement - we should simply honor GOD's ways. Matthew 5:17-19; Malachi 3:6; II Corinthians 9:6-15