"For if we sin willfully after we have received the knowledge of the truth, there no longer remains a sacrifice for sins, 27 but a certain fearful expectation of judgment, and fiery indignation which will devour the adversaries. 28 Anyone who has rejected Moses’ law dies without mercy on the testimony of two or three witnesses. 29 Of how much worse punishment, do you suppose, will he be thought worthy who has trampled the Son of God underfoot, counted the blood of the covenant by which he was sanctified a common thing, and insulted the Spirit of grace? 30 For we know Him who said, “Vengeance is Mine, I will repay,” says the Lord. And again, “The LORD will judge His people.” 31 It is a fearful thing to fall into the hands of the living God."
Misreading these verses has led many to despair. Who among us has not sinned willfully, after believing in Jesus Christ? Is there really no forgiveness left for us, then? Hebrews speaks here of forsaking Christ, going back to Judaism and counting Christ’s blood as common. In that case, you are not a believer. You aren’t under the saving blood of Jesus. If you look to temple animal blood instead of Christ’s blood for your covering, there is nothing left for you but punishment and judgment by God. These days we aren’t very tempted to look to ritual blood to save us. But we may be looking to our own blood, sweat and tears to save us. The point of these verses isn’t to scare us into repenting, but to point us to the blood of Jesus Christ. Far better to have a healthy fear of God now, that draws us to the cross of Jesus, than to dread God’s coming judgment because we stopped fearing God.
So this warning is first of all for the one who is sinning willfully and doesn’t care. God’s vengeance is coming on them. For us, who have sinned, but are sorry and are looking to Jesus, who are coming now in repentance, we need not fear such a judgment. We do not confess our sins to avert a dreadful sense of impending doom. We confess our sins because we should, because we are grieved – from a fear of God - at offending our Lord.