then I said Behold I have come as is written in the scroll of the bible, it is written about me, to do your will O God behold I have come to do your will... (Hebrews 10:5-10)
Before Jesus came into the world, sacrifice and offerings was no longer God's will, having not taking pleasure in these offerings so when he says "I have come to do your will..." he does away with the first in laws and sacrifices and offering "to establish the second in which will we exist holy through the offering of the body of Jesus Christ once and for all" (Hebrews 10:5-10).
just as Christ loved us and gave himself for us, as a fragrant offering and sacrifice to God (Ephesians 5:1-2)
Jesus's sacrifice and offering brought in a new covenant. "There is an annulment of the former commands as it is weak and useless (for the Law made nothing mature) now, the introduction of a better hope through whom we draw nigh" (Hebrews 7:18-19). This whole passage is to establish Jesus as a high priest on the order of Melchizedek. Because the old testament scriptures that the Messiah would be a descendant from Judah, and to the extent Moses said nothing about priests. Maybe we have hindsight the author did not have as we know Mary was cousins to Elizabeth whose husband was a priest. So there exists in Christ a priestly linage but nonetheless, the argument the author makes is sound. Jesus exists a priest on the order of a higher oath, God's oath (Hebrews 7:20-22).
On a side note, some people use this passage and the old testament passage it refers to, Genesis 14, to justify tithing in the new by saying it proves tithing existed before the Law. But this has no substantial grounds and in fact we read "if therefore maturity existed through the Levitical priesthood (for under it the people received God's Law) what further need of a kind of priest to arise according to the order of Melchizedek? And rather not it would be said according to the order of Aaron? For the priesthood is altered coming into existence from necessity, because of the alteration of the Law as well" (Hebrews 7:11-12).
The Law and service in the temple were a integral part, so if the Law changed so would there be an alteration of the priesthood, which states tithing is part of the offering to God in the temple which service was clearly defined under the Law (Deuteronomy 14:22-24). Thus priestly service in the temple, offering, sacrifices, and tithing would be altered if the Law is altered which it has been. So tithing doesn't exist in the new covenant. And since the Law was a shadow of that to come, we can understand what is to come in tithing, just as we do in the sin, guilt, burnt, food and incense offering in regards to the atonement for sin, propitiation for sin, and imputed righteousness and partaking of holiness through the body of Christ.*
And it existed more obvious if according to the likeness of Melchizedek another priest arises who does not according to a Law coming into existence in carnal commandments rather according to power of an indestructible life(Hebrews 7:15-18)
We stand on a better oath and promise, having a high priest who stands for all time, not according to the Law but a better promise and who was a body prepared for God's use, living an indestructible life without sin so to be acceptable sacrifice and offering and tithe. Who is able to save us completely those who draw near to him. We do not stand on weak and useless things that had no power to atone for sin nor appease God's wrath and anger toward sin, nor truly partake of the sacrifice and offering so to exist in holiness before God eternally thus existing perfect and mature partakers of God's nature. We stand on a better covenant that has power to atone for sin, cleanse the conscience before God so that we could in confidence approach him and receive grace and mercy as needed.
No, the Law and serving in the temple were weak and useless because of the sinful nature of man who had a carnal mind and had no power to obey God's laws which were spiritual. But as it was written in the book, behold Jesus said I have come to do your will, a body you prepared for me. Now, in the body of Christ we partake of holiness and can approach God holy and blameless in his presence in love, just as he chose us for this purpose before he created the world. Now, as spiritual being raised and seated with Christ in the heavenlies we have power to obey God's laws so to perform works of righteous that please God. But we exist in a body not yet redeemed so we have a reasonable service and sacrifice pleasing to God.
therefore become imitators of God like as beloved children and walk in love just as Christ loved us and gave himself for us, as a fragrant offering and sacrifice to God (Ephesians 5:1-2)
Christ loved us and gave himself for us, a fragrant offering and sacrificed to God. No longer does God desire sacrifice and offering and tithings... he desires a body to do his will. Therefore like as Christ let us present to God a fragrant offering and sacrifice that is pleasing to him. This is our reasonable service to present the body a living sacrifice, holy, acceptable to God (Romans 12:1-2). We are to be transformed, renewed in the spirit of our minds so we are approved, having the mind of Christ that can discern and accept God's will so we bear fruit of good works pleasing to God.