What covenant applies to us Gentiles then? You have the old covenant relating exclusively to the Jews. You have the new covenant relating exclusively to the Jews.
The reality is, the new covenant relates to all men, not just physical Israel.
You are butchering Scripture to support your error.
Jesus said in Mark 14:24, "This is my blood of the new testament, which is shed for many."
Plainly, it is not just restricted to Jews; it was for the Gentile equally, without it they would have no hope.
The international Church is instructed in 1 Corinthians 11:23-26, "For I have received of the Lord that which also I delivered unto you, That the Lord Jesus the same night in which he was betrayed took bread: And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me. After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me."
If the Gentile has no part in the new covenant why is he told to continually remember it and appreciate it?
Hebrews 13:20-21 declares, "Now the God of peace, that brought again from the dead our Lord Jesus, that great shepherd of the sheep, through the blood of the everlasting covenant, Make you perfect in every good work to do his will, working in you that which is wellpleasing in his sight, through Jesus Christ; to whom be glory for ever and ever. Amen."
Are we believing Gentiles not also the sheep of the Shepherd, along with the believing Jews? Is there not now just one fold of believers (John 10:16)? Are not all the sheep accepted equally without partiality into this covenant grouping to partake of the same heavenly blessings? With your reasoning, you have a divided sheep fold. You have a small minority of sheep - the believing Jews - enjoying the new covenant blessings and the vast majority - the Gentiles - totally excluded? This theory is majorly flawed.
Please consider. If there is no new covenant outside of Christ, then the new covenant is exclusive to the Church, because only the Church is in Christ. If only believers in Christ (the Church of Jesus Christ) are in the new covenant, then only believers in Christ (the Church of Jesus Christ) can fulfil Jeremiah’s prophecy. To conclude that the Jeremiah’s prophecy is fulfilled outside of the Church is to conclude that those who do not believe in Christ (the Church of Jesus Christ) are in the new covenant, which we all know is preposterous.