Hebrews 10:1-2 NASB95
For the Law, since it has only a shadow of the good things to come and not the very form of things, can never, by the same sacrifices which they offer continually year by year, make perfect those who draw near. [2] Otherwise, would they not have ceased to be offered, because the worshipers, having once been cleansed, would no longer have had consciousness of sins?
The basic flow of thought in Hebrews 8 – 12 is that in the new covenant the perfect sacrifice of the blood of Christ perfectly cleanses us and therefore frees us from a consciousness so that we can live by faith, and living by faith is fixing our eyes on the Lord Jesus who is the author and perfecter of faith.
It is impossible to walk in childlike faith if you’re walking around all the time with a sin consciousness. To walk in childlike faith is to live with a Christ consciousness that is continuously looking to Him, who is the author and the perfecter of our faith in any situation. To live with the sin consciousness is to constantly feel disqualified to experience any of God’s favor because you don’t feel like you deserve it, which of course, means that you think you can earn it by being good enough. The new covenant tells us that we are in union with Christ, and therefore we fix our eyes on Him and rest in His faith who always is qualified and deserves God’s favor. Living in the covenant of grace is knowing that God in Christ has done everything for us that he has required of us so that we can receive by faith the benefits of His work. Our great action is to believe. Living with a sin consciousness is not humility; it is simply unbelief.