You have absolutely no evidence biblically or otherwise that salvation happens after death, Your group only has a few out of context verses to hang your erroneous belief on. You cannot take Romans 6:7 in a vacuum.
“What shall we say then? Are we to continue in sin so that grace may increase? May it never be! How shall we who died to sin still live in it? Or do you not know that all of us who have been baptized into Christ Jesus have been baptized into His death? Therefore we have been buried with Him through baptism into death, so that as Christ was raised from the dead through the glory of the Father, so we too might walk in newness of life. For if we have become united with Him in the likeness of His death, certainly we shall also be in the likeness of His resurrection, knowing this, that our old self was crucified with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin; for he who has died is freed from sin.”
Romans 6:1-7 NASB1995
What shall we say then? Are we to continue in sin so that grace may increase? May it never be! How shall we who died to sin still live in it? Or do you not know that all of us who have been baptized i
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The death here refers to dying in Christ after being buried with Him through baptism and become united in Him in the likeness of His death. His believers are no longer slaves to sin SO he who dies is free of sin. This verse does NOT help you.
The rest of the verses that you posted also does not help you at all. Paul does not teach that salvation is by the grace of God through faith (Eph. 2) and then teach that faith is not necessary because all will be saved at the end. What you are peddling is an illogical and unbiblical teaching that was deemed anathema during the 5th Ecumenical Council in 553ad.