Do you mean the New Covenant in Jesus' blood does not surpass the Abrahamic Covenant?? I would think "surpass" means to be better than and to do better than.
And I think the Covenant of Jesus is better than what is in the Abrahamic Covenant, since Romans 8:29 says we are destined to be conformed to the image of Jesus, plus in the Lord's prayer in John 17 Jesus claims how we are loved even as our Father loves Jesus.
And I don't think these blessings are mentioned in the Abrahamic Covenant.
So, I'm not sure what you mean. Even if they both are unconditional, the newer one can be better. Also, how we understand the Abrahamic Covenant can be surpassed by knowing the New Covenant.
So, if I understand this right
@Daniel Marsh > the New Covenant would not replace the Abrahamic Covenant, but it would/might surpass how we have understood the promises to Abraham.
This could get interesting . . . in case the LORD has promised land to Abraham, among other things. Ones might take this to mean only to Israelites. But what about how the New Covenant says we who are of faith are children of faithful Abraham (Galatians 3:7,9 & 29)? Could this mean we in Jesus are promised the land??? Paul says > "all things are yours", in 1 Corinthians 3:21-22.
Daniel, I get this by what I am finding in the Bible. So, I am not offering this based on any writer that I know of, just in case there is anyone who has published anything like this.