Part of fulfilling the law is bringing an end to it. If were going to keep the Law of Moses commandment to tithe we may as well keep the other commandments which include observing Jewish feasts and holy days, offering animal sacrifices, shunning unclean meats, circumcision, and keeping the Sabbath day etc. See my point? When Jesus fulfilled the law He obeyed it, brought an end to it, and then introduced a grace/new covenant form of it. For example, Jesus obeyed the command to keep the feast of passover, then he fulfilled it by becoming the new covenant form of the passover lamb and abolishing the old covenant command to keep the feast of passover each year. In a similar way, Jesus obeyed the law of tithing throughout His life, and then brought an end to it on the cross when He abolished the law with its impossible requirements, and the type of giving that the new covenant church were a part of was not tithing, but giving generously (Acts 11:29).
Here are some verses that prove the law has truly been abolished and done away with:
For sin shall not be your master, because you are not under law, but under grace. (Romans 6:14)
But now, by dying to what once bound us, we have been released from the law so that we serve in the new way of the Spirit, and not in the old way of the written code. (Romans 7:6)
Christ is the end of the law so that there may be righteousness for everyone who believes. (Romans 10:4)
know that a man is not justified by observing the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by observing the law, because by observing the law no one will be justified. (Galatians 2:16)
Clearly no one is justified before God by the law, because, The righteous will live by faith. (Galatians 3:11)
So the law was put in charge to lead us to Christ [ Or charge until Christ came] that we might be justified by faith. (Galatians 3:24)
So Christ has really set us free. Now make sure that you stay free, and don't get tied up again in slavery to the law. (Galatians 5:1 NLT)
The former regulation [the Law of Moses] is set aside because it was weak and useless (for the law made nothing perfect), and a better hope is introduced, by which we draw near to God. (Hebrews 7:18-19)
But now in Christ Jesus you who once were far away have been brought near through the blood of Christ. For he himself is our peace, who has made the two one and has destroyed the barrier, the dividing wall of hostility, by abolishing in his flesh the law with its commandments and regulations. His purpose was to create in himself one new man out of the two, thus making peace, (Ephesians 2:13-15)
When you were dead in your sins and in the uncircumcision of your sinful nature, God made you alive with Christ. He forgave us all our sins, having canceled the written code, with its regulations, that was against us and that stood opposed to us; he took it away, nailing it to the cross. (Colossians 2:13-14)
Tithing is a legalistic command that was abolished at the cross. We are now required to give generously, sacrificially, cheefully, and consistantly because this is what the new covenant church did. Tithing was a complete non issue for the new testament church. God no longer requires 10% He requires a personal spirit of generosity. (i believe that true spirit filled generosity will always result in giving more than 10% - however we must never make that a law, because if we do we are simply oveying the law of tithing all over again).
If one struggles with motivation to give generously when there is no new covenant commandment to give anything at all (2 Cor 8:7-8 NLT) then one needs to get a revelation of the power, purpose and impact that one's wealth can have on other people's lives, and one needs to understand that they will only reap according to the size of seed they sow (2 Cor 9:6).
The law of tithing has been abolished. God has freed us from this legalistic command of the old covenant.
God bless you as you study His Word!