(sorry I hadn't replied directly to this post of yours at the time)
You quoted Jeremiah 31:31-34, as quoted in Hebrews 8:8-12, then stated:
We see in that covenant ;
1. the new heart, new birth, new creation
2 forgiveness of sins
3. adoption
There is not one other covenant in all of scripture that competes with it.
To which I replied, sure there is, the new covenant in Jesus' blood. But it's not a competition. You replied:
If you splice them up into bits - then the 'New Covenant in my blood" stands alone and is excluded from the "New Covenant" as scripture records it in both Jer 31 and Hebrews 8.
No one is splicing them into bits. I am discerning they are two different covenants with their own set of promises directed to two different named parties to take effect at two different times. That's the plain reading of the two covenants. Obviously.
IN that case your "other" New Covenant and has no forgiveness of sins, no new birth, no new creation, no new heart, no adoption. It is just 'the New Covenant in my blood". period.
Uh, all those blessings you list are
explicitly defined in the NT as coming by way of the new covenant in Jesus' blood, apart from Jeremiah 31 -- 1) forgiveness of sins: "In (Christ) we have redemption, the forgiveness of sins," Colossians 1:14; 2) new birth: "God...has caused us to be born again to a living hope through the resurrection of Jesus Christ," 1 Peter 1:3, 3) new creation: "If anyone is in Christ, he is a new creature," 2 Corinthians 5:17; 4) new heart: "refresh my heart in Christ," Philemon 1:20; 5) adoption: "(God) predestined us to adoption as sons through Jesus Christ to Himself," Ephesians 1:5.
The entire New Testament (aka New Covenant) writings are filled with descriptions and revelations of the blessings that come through Abraham's Covenant of Blessings on All the Nations Through His Promised Seed Heir Jesus Christ, aka, the New Covenant, aka, the Better Covenant.
But if you allow it to stand in context where it is adding more detail the explicitly stated "New Covenant" of Jer 31:31-34 (which is the context Jesus' hearers would have had for that term at the time He spoke it) - then it is shedding more light on the one-and-only New Covenant. Which would look a lot like "another gospel".
Not sure what you mean by "Jesus' hearers... at the time He spoke it," but nevertheless, there is not "another gospel." I don't know why you keep saying that. There is one gospel, as we both agree there is, and it comes through the
Abrahamic Covenant of Blessings Come to the Nations Through the Promised Seed Heir Jesus Christ By His Shed Blood, as read at Genesis 12:3, Genesis 17:2-7, Genesis 22:16-18, Isaiah 55:1-9, Mark 14:24, Luke 22:20, 1 Corinthians 11:25 ("This cup is the
new covenant in My blood"), Galatians 3:6-18 ("Christ... (became) a curse for us... in order that
in Christ Jesus the blessing of Abraham might come to the Gentiles....(by) a covenant previously ratified by God"); Hebrews 7:22 ("Jesus has become the guarantee of a
better covenant"), and Hebrews 8:6 ("He is... the mediator of a
better covenant, which has been enacted on
better promises").
That Israel gets some blessings in the kingdom through a New Covenant that replaces the Mosaic Law Covenant, by God placing that Law within their hearts, doesn't change any of the blessings that come through the Better Covenant in Jesus' Blood.
After all, that Ishmael was promised to be blessed, to be fruitful, to become the father of twelve princes, to be made into a great nation, does not mean that Isaac's promises for the exact same things were thereby nullified, no more than when the Law Covenant came that the Covenant of Blessing on all the nations through Abraham's Promised Seed Heir would be nullified.
God is free to make a covenant with the House of Israel exclusively if he wants, and that covenant in no way nullifies the promises of another covenant He makes that enures to the benefit of the whole world.