The law is a shadow of the good things to come and can never perfect those who draw near by the same sacrifices year after year; those sacrifices only remind people of sins, since the blood of bulls and goats cannot take them away. So Christ, quoting Psalm 40, says that God prepared a body for him and that he came to do God's will. By that will we are sanctified through the offering of his body once for all.
Every priest stands daily offering the same sacrifices; Christ offered a single sacrifice for sins and sat down at God's right hand. By that one offering he has perfected for all time those who are sanctified, and since Jeremiah's new covenant promises to remember their sins no more, there is no longer any offering for sin.
Then comes the exhortation: we have confidence to enter the holy places by the blood of Jesus and by the new and living way, and a great priest over the house of God. Let us draw near with a true heart in full assurance, hold fast the hope, stir one another up to love and good works and not neglect meeting together. Whoever sins deliberately after knowing the truth and tramples the Son of God faces a fearful judgment.
The author recalls earlier days, when the readers joyfully endured reproach and the plundering of their property, and asks them not to throw away their confidence. The righteous shall live by faith, as Habakkuk says, and they are not of those who shrink back but of those who believe to the saving of their souls.