Since the Greek word is apostasia, how can it not have anything to do with apostasy, a falling away from the faith?
μή τις ὑμᾶς ἐξαπατήσῃ κατὰ μηδένα τρόπον· ὅτι ἐὰν μὴ ἔλθῃ ἡ ἀποστασία πρῶτον, καὶ ἀποκαλυφθῇ ὁ ἄνθρωπος τῆς ἁμαρτίας, ὁ υἱὸς τῆς ἀπωλείας
The only event to precede the Resurrection/Rapture is the great falling away.
μή τις ὑμᾶς ἐξαπατήσῃ κατὰ μηδένα τρόπον· ὅτι ἐὰν μὴ ἔλθῃ ἡ ἀποστασία πρῶτον, καὶ ἀποκαλυφθῇ ὁ ἄνθρωπος τῆς ἁμαρτίας, ὁ υἱὸς τῆς ἀπωλείας
The only event to precede the Resurrection/Rapture is the great falling away.
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Acts 21:21
"They have been informed now about you that apostasy you teach from Moses those among the gentiles all the Jews telling not to circumcise them the children nor in the customs to walk"
Paul preaching the gospel of salvation in Christ Jesus is "apostasy you teach"? No. Paul was teaching "APOSTASIAN".....DEPARTURE (NOUN). Departing from obsolete, ineffective damning useless Mosaic Judaism.