The sacrifices under the old covenant could not purge (cleanse) sin, they just reminded them of their sins, making the consequences of their sin null and postponed, until the real sacrifice of the Lamb of God could take place. Because it was not possible for the blood of bulls and goats to take away sin. The repetition of the sacrifices is evidence to the author that they were inferior and served as a constant reminder to the Jews that their sins were not adequately dealt with. As proof of the inadequacy of these sacrifices Psalm 40:6-8 is cited.
Christ came to do His Father’s will and take away the sins of the world with His own blood. In doing this, Christ satisfied all the requirements of the law, fulfilling it (Matt 5:17-18), removing the first covenant and establishing the new (second). Now that sin has been sufficiently purged, man can be sanctified (to purify the soul and set us apart) so that we can now draw near to God. The Hebrew writer now establishes their confidence in Christ and the forgiveness of sin by reminding them of Jeremiah’s prophecy of God’s promise of a new covenant which was inspired by the Holy Spirit (Jer. 31:33,34; see notes ch. 8). So when our sin is completely forgiven, there is no need for any more sacrifices. For the remainder of this letter, he pleads with them to draw near to God with full confidence, to remain steadfast in this new living way; he encourages spiritual maturity and love, and continues his warning of apostasy. We can now have complete confidence (boldness) in the ability to approach God because Christ has entered the Most Holy place for them, through the veil by His own blood. This ability to finally approach God through His Son’s sacrifice is the “new and living way”, 10:20. What did the veil represent? When was it removed for us? (see Matt 27:50-51)
Drawing back from this new covenant is the same as denying Christ, His great sacrifice and indeed God Himself. The writer provides us a familiar quote from Deut. 32:35. God will judge and repay them for their unrighteous deeds. So our respect to the extent of awe is what helps our boldness in prayer, to be real, without becoming flippant and so casual that we talk to God, as if he is a “buddy”. He is not, but rather He is the Almighty and His Son is King of kings & Lord of lords. The writer now reminds them of how zealous they were when they first received the truth. He exhorts them to remain patient and steadfast knowing in the end they will receive the promise. Therefore, do not draw back!
The phrase “as you see the day approaching” (10:25) has induced much controversy. It is not the destruction of Jerusalem, even though certainly this would be a calamitous time, but not a particular day and it would be accompanied by definite signs (Mt 24:4-28). Jerusalem’s destruction was between 14 April – 9 September 70AD, with a note from secular historians that the temple stones were thrown in the streets on the 9th of August 70AD. But the warning about “the day”, is general, it could have reference to the day of judgment. But some object to this explanation on the grounds that no one will “see” that day approaching. But we understand that life is brief and uncertain (Jas 4:13-14), and spiritual maturity brings a sense of urgency. Truly “our salvation is nearer than when we first believed” (Rom 13:11). So we should take advantage of every opportunity to encourage weaker Christians who are drifting away from the Lord. “The Day” is most likely the Lord’s Day, Sunday, Rev. 1:10. Get ready and stay ready in prayer!