How do the sheep who survive the tribulation avoid taking the mark of the beast during the tribulation? The way the scripture reads “And he had power to give life unto the image of the beast, that the image of the beast should both speak, and cause that as many as would not worship the image of the beast should be killed.” leads me to believe that those who do not take the mark will be killed by the beast. Which means there would be no believers left, unless of course this is what Yeshua meant when he said he would shorten the days for the elect’s sake because if he didn’t, there would be no flesh left alive.
I think the phrase “unless those days be shortened” is a weak translation given the context of the passage and the numerous times in the Bible where the Great Tribulation is described as being 1260 days, or 42 months, or 3 1/2 years long. Using Earth’s original 360 day calendar, these are all equivalent terms. Therefore the Great Tribulation won’t be cut short.
I believe the Lord meant something to the effect that if the Great Tribulation was allowed to run its full course no one would be left at the end, but for the sake of the elect He will return at the appointed time to put a stop to it.
According to most estimates, about half of the post rapture world will perish in the end times judgments. That means the other half will still be living when the Lord returns. From the Sheep and Goat judgment of Matt. 25:31-46 we learn that some will be believers (sheep) and the rest won’t (goats). The believers will have survived primarily because the anti-Christ won’t have had time to hunt them all down and kill them.