This is speaking of the people that will be standing in the "Time of Jacob's trouble" after the plagues start. The Bible calls them the 144,000. You may have heard me call them the "Gideon band" on occasion. They are trusted by God to be able to stand during the plagues perfectly, wherein the other Christians that were too weak to stand in such a trying time, but are still worthy of Heaven, they will have to die a martyrs death. Reason being is, they are not strong enough to handle the way the people of the world will treat them or their loved ones during the plagues. They would fall into sin for a multitude of reasons we as Christians cannot comprehend clearly enough to comment on. But the Lord. does know exactly what will happen. He loves them so much, He actually allows them to die before that day comes so they will not be destroyed by Satan. They will resurrect when Jesus returns to gain their eternal reward. Many of these dear souls die via the guillotines of course.
By the way, there are already 30,000 guillotines on U.S. soil right now! When the plagues start, judgment is DONE. This is why Jesus says at that exact time in Heaven just before He returns to earth, "He that is unjust, let him be unjust still: and he which is filthy, let him be filthy still: and he that is righteous, let him be righteous still: and he that is holy, let him be holy still." (Revelation 22:11) In other words, those that are without Christ and wicked, (unjust / filthy) these will remain that way when Jesus speaks these final words. However, those that are true Christians and capable of proving to the Universe that God can and has created a people that will trust in Him even in intense times, (the 144,000) these will remain holy and without sin from this day forward. (righteous / holy) Satan will not be able to tempt them anymore. They proved themselves worthy in their loves leading up to this day. Therefore their faith is blessed to allow them to stand during the plagues when God's wrath falls upon mankind. If I am called to stand during these days it will be at this time that I stop preaching to try and get people to find Jesus. Once the plagues start, no one will be able to be saved anymore and no one that is saved will be lost. Whoever is unjust remains that way, and whoever is holy remains that way. Reason being, judgment ended on that day and now the "reward" for their sins is upon the wicked in the way of plagues, and finally death. Our reward will be at the end of the plagues when Jesus gives us new bodies and eternal life.