[yatros from flatwater]

I don't look to the OT for this position. The NT is sufficient. The Lord Jesus Christ is the Jehovah of the OT. The Jehovah of those who call themselves Jews today is not the Lord Jesus Christ, therefore not the Jehovah of the OT. Not difficult.

I'll second Risha's motion.

If "The NT is sufficient", how does your position differ from one which would hold that the Koran supersedes prior revelations? Jesus, or more properly, Y'shua, based all his teaching upon the Torah, Prophets and Writings, as well as some oral Torah ("you have heard it said") How would you say that Jews of today recognize a different "pagan" "god" than that set forth in those same teachings.

In other words, Torah must be recognized as the basis for instruction about God, the Universe and Everything or one is no better off than a "prophet" who claims that his new personal revelation is better than yours.

[fox martyr son]

The NT fully affirms all that is written in the OT.
The Koran makes the claim that previous revelations are corrupt and thus contradicts them.
Your comparison of the NT succession to the OT and the Koran succession to the NT/OT hasn't been thoughtful.