I've read through revelation a couple of times, and admittedly, it is difficult to tell which lines are to be taken literally and which symbolically. It was written based on a dream after all.
Here's my guess about the 'mark of the Beast'. I don't think that it is a physical mark...right hand and/or forehead might have symbolic meanings in other scriptures I'm unfamiliar with. If we are to take Revelation as literal as possible, I think the mark might refer to international banking--meaning that countries and corporations that find favor with the international elite (like the world Bank, or the Federal Reserve) will have access to currency. Those who are out of favor will be cut off and be unable to buy, sell, or trade outside the black market.
How about it just being literal?
How long do you think it would take to physically mark every person who worships the beast?
Revelation 13
16 He causes all, both small and great, rich and poor, free and slave, to receive a mark on their right hand or on their foreheads,
Notice the Word says "all", not just some, but "all". That's a lot of people. The world population right now stands at 6,776,331,434. That's well over 6 billion. Even if you cut that number in half, that's still a lot of people. And those numbers are todays population. What will those numbers be next year, five years, or ten years from now?
That's only one item to be considered when we look at what the mark of the beast will be.
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None of what I'm saying is etched in stone. I'm just putting it out there for consideration.
As I stated, if there are other interpretations, I would like to hear them. If you believe it to be taken as literal, let's discuss the possibilities of how that can be accomplished.
Instead of arguing about who's right and who's wrong, let's discuss it and see where it takes us.