Quote:
“..so that the image of the beast might even speak and might cause those who would not worship the image of the beast to be slain.
There’s your answer.”
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Which relates to those left behind because they were not AT THE TIME OF THE RAPTURE Born Again. But converted to Christianity AFTER the Rapture for a very large harvest of souls who were then beheaded for their Testimony of the Lord Jesus Christ and received salvation through the Blood of the slain Lamb.
A number that John wrote unable to be counted.
There's your answer.
Rev 13:15 which you cite is pretty inclusive but the net comes up empty if the church is no longer on earth.
Nothing in Rev 13 locates the church on earth but much between Rev 4 - Rev 19 describes a persecuted religious body which on close inspection is different from the present church yet whose believers, most of who will be martyred between Rev 4-Rev 19 are saved.
Where the present church relies on belief in the death burial and resurrection of Jesus for salvation, this body of believers during the tribulation relies on a similar yet different gospel partly described in Rev 14.
Rev 14:6 Then I saw another angel flying in the midst of heaven, having the everlasting gospel to preach to those who dwell on the earth—to every nation, tribe, tongue, and people—
Rev 14:7 saying with a loud voice, “Fear God and give glory to Him, for the hour of His judgment has come; and worship Him who made heaven and earth, the sea and springs of water.”