How are we to understand the contradiction that Yom Kippur is to be observed as a "statute forever" (Lev. 16:29) while the New Testament emphatically states that Yeshua puts an end to animal sacrifice and now is our eternal atonement (Heb. 9:12; 24-26)? To begin we must note that this contradiction only arises when we make the (false) assumption that the Sinai covenant could never be abrogated, which would imply that a new covenant is logically impossible. If we can only relate to God through the covenantal terms given at Sinai, in other words, then the Levitical priesthood (alone) serves to mediate us before God, and there would be no need for a new covenant based on the better priesthood and promises of the Messiah (Heb. 8:6). Nevertheless, the new covenant was clearly foretold throughout the Torah, the writings, and the prophets, and the rabbinical assumption that the Torah is "immutable" is therefore false. We can understand this by an analogy: If an employer makes a contract with an employee with certain provisions and conditional benefits that are subject to annual review, but later rescinds that contact and offers a new one with far better benefits, there is no contradiction involved. In our case a real contradiction would be, "you must observe Yom Kippur forever," and then - in the very same contract - later read, "you no longer need observe Yom Kippur forever."
Since the Torah says of the Yom Kippur ritual, "this shall be a statute forever (ΧΦ»Χ§ΦΌΦ·Χͺ Χ’ΧΦΉΧΦΈΧ) for you, that atonement may be made for the people of Israel once in the year because of all their sins" (Lev. 16:34), it is urgent for us to explore what "forever" might mean in this case, especially in light of the atonement given in Yeshua. First, we note that the Hebrew word translated "forever" is olam (Χ’ΧΦΉΧΦΈΧ), which is derived from a root verb alam (Χ’ΦΈΧΦ·Χ) that means "to conceal" or "to hide." Olam may have its origins using spatial imagery, a distance so vast that it is unseen, beyond the horizon, and therefore it can also mean "world." When it is applied to the terms of the Sinai covenant (and the Tabernacle represents the "ritual expression" of that covenant), the word means perpetual, ongoing, etc., in that domain or "world." It is interesting to note that the Jewish sages never regarded "olam" as unchangeable, since in the world to come Torah from Zion (Isa. 2:3). For more on this imprtant point, see the article "Olam HaTorah: The World of the Torah."
Second, we must remember that Torah (ΧͺΦΌΧΦΉΧ¨ΦΈΧ) is a "function word" that expresses our responsibility in light of the covenantal acts of God, and if you choose to relate to God by means of the Sinai covenant, you are liable to the terms and provisions of that contract (e.g., niddah laws, blood ritual laws, tithing laws, agricultural laws, etc.), and this includes being liable to the enumerated curses for disobedience. The covenant at Sinai is indeed eternal and never can change - it is brit olam, a perpetual covenant - but if you choose to abide by its terms, you are responsible for your side of the contract... The Book of Hebrews states: "When there is a change in the priesthood (ΧΦ·ΧΦΌΦ°ΧΧΦΌΧ ΦΌΦΈΧ), there is necessarily (αΌΞ½α½±Ξ³ΞΊΞ·) a change in the Torah as well" (Heb. 7:12). The Levitical priesthood expresses the Torah of the Covenant of Sinai (ΧΦΌΦ°Χ¨Φ΄ΧΧͺ ΧΦ°Χ©ΧΦΈΧ ΦΈΧ), just as the greater priesthood of Yeshua expresses the Torah of the New Covenant (ΧΦΌΦ°Χ¨Φ΄ΧΧͺ ΧΦ²ΧΦΈΧ©ΧΦΈΧ).
Third, Yeshua our Messiah came to deliver us from sin and to establish the new covenant with God, which both transcends the moral law of Sinai and provides an entirely new way to be in relationship with God by the power of the Holy Spirit. The new covenant sets us free from the terms of Sinai (by the death of the Testator, Heb. 9:15) so that we might serve God in a new and better way (see Jer. 31:33; Rom. 7:1-6; Heb. 8:6; Rom. 9:31-32; Acts 13:39; Gal. 4:21-5:1). We "die" to the terms of the former contract to serve God in a new and powerful way (Rom. 7:1-4), with the inner intent of the law written upon our hearts (Jer. 31:31-33). This is the "deeper Torah" that goes back to the original covenant made in the Garden of Eden (for more on this, see "The Gospel in the Garden").
Fourth, Yeshua is the King, the Lawgiver of Torah, and its Substance: he did not come to destroy the Law and the Prophets, but to fulfill their message and meaning (Matt. 5:17-18; Rom. 10:4). As the King, he has the authority to annul contracts with his subjects, and he has the authority to implement new agreements based on his sovereign will... The Torah of Moses commanded, "Thou shalt not kill..." but the King of Torah (ΧΧΧ ΧΧͺΧΧ¨Χ) went to the heart of the matter, explaining that murder was a symptom of the deeper sin of anger...
Finally, those who follow the law of Moses simply cannot keep the Day of Atonement as clearly commanded in the Book of Leviticus, nor have Jews been able to do so since 70 AD, after the destruction of the Second Temple as foretold by Yeshua (Matt. 24:2; Luke 19:41-4). Note that this was by divine design, since the way into the Holy of Holies (i.e., kodesh hakodashim: Χ§ΧΦΆΧ©Χ ΧΦ·Χ§ΦΌΦ³ΧΦΈΧ©ΧΦ΄ΧΧ) was not yet open for all as long as the "outer tent" still stood (i.e., the Levitical priesthood as the ritualistic expression of the covenant made at Sinai), since that was symbolic of "the present age," or the "dispensation that was passing away" (Heb. 8:13, 9:8-9; for more, see "The Parochet Rent in Two"). Despite the later invention of "Judaism without the Temple," the life is indeed "in the blood" (Lev. 17:11) and in Messiah we are given fulness of life! Only Yeshua gives us true atonement, and that's the true Torah of the LORD! The redemption obtained by animal sacrifices was merely provisional and symbolic, "for it is impossible for the blood of bulls and goats to take away sins" (Heb. 10:4). For eternal remedy something far greater was needed, namely, the sacrifice of God Himself. Consequently, when Yeshua came into the world, he said, "Sacrifices and offerings you have not desired, but a body have you prepared for me," and "'Behold, I have come to do your will, O God, as it is written of me in the scroll of the book" (Heb. 10:5,7). As the Book of Hebrew states: "We have an altar, whereof they have no right to eat who serve the Tabernacle" (i.e., the Levitical system of worship). We are cleansed from our sins and made eternally right with God beause of the cross of Yeshua...
The bottom line is this. We have a greater High Priest who intercedes for us by means of his own shed blood within the true Holy of Holies, "made without hands," in the olam of reality. We do not mix the covenants of God, for this leads to double-mindedness and is regarded as spiritual adultery (Rom. 7:1-4). It is chillul HaShem - the desecration of the Name above all Names - to turn away from the meaning and message of the cross of Messiah.
Note: We study the Yom Kippur avodah and the various rituals of blood atonement to better understand the meaning of Yeshua's sacrificial death for us as God's High Priest of the New Covenant. Moreover, as I've explained elsewhere on this site, Yom Kippur prophetically pictures the "Day of the LORD" or the Day of Judgment in Acharit Ha-Yamim (the End of Days). The heavenly shofar blasts heard at Mount Sinai will be reissued from Zion for all the world to hear. First will be the gathering together of those who follow the Messiah (i.e., those declared tzaddikim because of the merit of Yeshua's sacrifice), and then God's war against Satan and the world system will begin, culminating in the long-awaited coronation of the King of King of Kings. After the judgment of the nations after the Great Tribulation, ethnic Israel will be fully restored to the LORD and their sins will be completely purged (Matt. 24). "All Israel will be saved" (Rom. 11:26). Yeshua will then physically return to Israel to establish His glorious millennial kingdom in Zion. Then all the promises given to ethnic Israel through the prophets will finally be fulfilled.