1.The Jews cannot evade the force of Jer. 31:31-34 which clearly indicates that the Torah is insufficient and thus revision is required,
“Jer 31:31 “See, the days are coming,” declares יהוה” ,when I shall make a new covenant with the house of Yisra’ĕl and with the house of Yehuḏah1, Footnote: 1See Heb. 8:8-12, Heb. 10:16- 17. Jer 31:32 not like the covenant I made with their fathers in the day when I took them by the hand to bring them out of the land of Mitsrayim, My covenant which they broke, though I was a husband to them,” declares יהוה .Jer 31:33 “For this is the covenant I shall make with the house of Yisra’ĕl after those days, declares יהוה :I shall put My Torah in their inward parts, and write it on their hearts. And I shall be their Elohim, and they shall be My people. Jer 31:34 “And no longer shall they teach, each one his neighbour, and each one his brother, saying, ‘Know יהוה ‘,for they shall all know Me, from the least of them to the greatest of them,” declares יהוה” .For I shall forgive their crookedness, and remember their sin no more.”
Why would Jeremiah indicate the need for a new covenant, not according to the Sinai Covenant if there was nothing wrong with the Sinai Covenant? John Owen states,
“Indeed this promise of a new covenant, diverse from that made at Sinai, or not like unto it, as the prophet speaks, is sufficient of itself to overthrow the vain pretences of the Jews [And the Ebionites] wherein they are hardened to this day. The absolute perpetuity of the law and its worship, that is, of the covenant at Sinai, is the principal, fundamental article of their present faith, or rather unbelief. But this is framed by them in direct opposition unto the promises of God. For let it be demanded of them, whether they believe that God will make another covenant with the church, not according to the covenant which he made with their fathers at Sinai. If they shall say they do not believe it, then do they plainly renounce the prophets, and the promises of God given by them. If they do grant it, I desire to know of them with what sacrifices this new covenant shall be established; by what priest, with what worship, it shall be administered. If they say that they shall be done by the sacrifices, priests, and worship of the law, they deny what they granted before, namely, that it is a new and another covenant; for the sacrifices and priests of the law cannot confirm or administer any other covenant, but that which they belong and are confined unto. If it be granted that this new covenant must have a new mediator, a new priest, a new sacrifice, as it is undeniable it must, or it cannot be a new covenant, then must the old cease and be removed, that this may come into its place. Nothing but obstinacy and blindness can resist the force of this argument…”.
Owen, Hebrews, Vol. 6, pg. 101-102
The best objection I have read from Jews concerning this passage is that verse 34 states that all will know the Lord. So why isn’t everyone saved? Ans. This passage is talking about the house of Israel and Judah which is partly spiritualized in Gal. 3 and Heb. 8 to refer to all in covenant with Yah through Messiah Yeshua, not every single human being. On the Jews own Sinaitic perspective why should all people be saved?
2. If the Torah was perfect and its purpose meant to be eternal and unchangeable, why did David prophesy in Psalm 110 of a priest to come, who would minister forever, after the order of Malkitsedeq and not the Levitical priesthood?
Psa 110:4 יהוה has sworn and does not relent, “You are a priest forever According to the order of Malkitseḏeq.”
Dear believer in Messiah, do not give the Jew an opportunity to bombard you with New Testament criticism regarding the book of Hebrews and its mention of this argument. Only mention the book of Psalms here to avoid the diversion.