We have an eternal high priest and an eternal sacrifice in Jesus Christ. The Law is no longer imposed externally, as it was in the old covenant, but written on the hearts of those who believe. Now, writes St. Paul in the Letter to the Hebrews, we must simply persevere in the Faith. When we doubt or draw back, we fall into sin.
Having therefore, brethren, a confidence in the entering into the holies by the blood of Christ; a new and living way which he hath dedicated for us through the veil, that is to say, his flesh, and a high priest over the house of God: Let us draw near with a true heart in fulness of faith, having our hearts sprinkled from an evil conscience, and our bodies washed with clean water. Let us hold fast the confession of our hope without wavering (for he is faithful that hath promised), and let us consider one another, to provoke unto charity and to good works: Not forsaking our assembly, as some are accustomed; but comforting one another, and so much the more as you see the day approaching.
For if we sin wilfully after having the knowledge of the truth, there is now left no sacrifice for sins, but a certain dreadful expectation of judgment, and the rage of a fire which shall consume the adversaries. A man making void the law of Moses, dieth without any mercy under two or three witnesses: How much more, do you think he deserveth worse punishments, who hath trodden under foot the Son of God, and hath esteemed the blood of the testament unclean, by which he was sanctified, and hath offered an affront to the Spirit of grace? For we know him that hath said: Vengeance belongeth to me, and I will repay. And again: The Lord shall judge his people. It is a fearful thing to fall into the hands of the living God.
But call to mind the former days, wherein, being illuminated, you endured a great fight of afflictions. And on the one hand indeed, by reproaches and tribulations, were made a gazingstock; and on the other, became companions of them that were used in such sort. For you both had compassion on them that were in bands, and took with joy the being stripped of your own goods, knowing that you have a better and a lasting substance. Do not therefore lose your confidence, which hath a great reward. For patience is necessary for you; that, doing the will of God, you may receive the promise.
For yet a little and a very little while, and he that is to come, will come, and will not delay. But my just man liveth by faith; but if he withdraw himself, he shall not please my soul. But we are not the children of withdrawing unto perdition, but of faith to the saving of the soul.
- Source: Douay-Rheims 1899 American Edition of the Bible (in the public domain)