The Body is a specific designation for the Church, not for believers of any other period (hence a mystery)
Once the fullness of the Gentiles has been arrived at, then the Body of Christ, His bride, will be complete and be removed.
Saved Jews of the Old Testament (and Tribulation) are friends of the bride, not the bride.(Jn.3:29)
It is the Gentiles who are being 'grafted into the Jewish tree' of salvation.(Rom.11,4)
The Jews have been set aside (mystery of hardening) while this new body, made up of mostly Gentiles is being formed.
Paul states that the Gentiles being saved and being changed from Gentile to Christian is to provoke the Jews to envy.
Salvation was always of the Jew,(Rom.3) but now the Gentiles are the ones being saved, while the Jews are blinded.
Yet, when the full number of Gentiles and individual Jews have been added to the church, then that body will be removed be wed to Christ (Rev.19:7-9)
Saved Jews and Gentiles of the Old Testament and Tribulation are not church, are not the Body of Christ, are not the Bride of Christ.
Thus, there are three groups of saved people, Gentiles, Jews and Christian.
Abraham is a saved Jew (not part of the Body)
Noah is a saved Gentile (Not part of the Body)
Paul is a saved Jew who became a Christian (part of the Body) the Eunich of Acts 8 was a Gentile who became a Christian (Part of the Body).
The church age began in Acts 2 and will run until the Rapture.
When the Body becomes complete (Rom.11:25) then the church will be removed and the Tribulation will begin which is a continuation of the Old Testament, and there will be saved Jews and Gentiles, but no Christians (no Body)