People have been freaking out about the concept of the mark of the beast ever since John wrote the Apocalypse. In our recent history Government issued IDs and Passports, Barcodes and recently - cashless payment systems such as credit cards and wire transfers, even cryptocurrencies have been labeled as the "mark of the beast".
RFID chips have recieved a special status since they are actually implanted inside the body and they can be used to replace most of the above mentioned technologies. Enthusiasts in several countries have already adopted this tech for the sake of convenience. This is scary because it brings us ever closer to the real thing, but I'm not sure we're quite there yet.
Lets consider what the bible says about the mark in Revelation 13:16-18:
"And he causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads:
And that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name.
Here is wisdom. Let him that hath understanding count the number of the beast: for it is the number of a man; and his number is Six hundred threescore and six."
The reason RFID chips are excellent candidates for the mark of the beast is because they are the size of a grain of rice, usually implanted inside the skin between your thumb and index finger which fits with Rev13:16 but the distinction is that the beast or the ruling world government demands these IDs to be implanted. The rest follows suit with regular IDs we have from our governments - we have our birth name, unique number for each individual person which is calculated on the date and location of our birth. The name of the beast simply represents our citizenship. Those born in the USA are given the name of Americans, those born in Canada - Canadians and so on. So, if for some reason all governments of the world suddenly decided to do away with plastic or paper IDs, passports, credit cards/bank accounts and instead issued every citizen their unique RFID-Chip implant or possibly Nanowire-tattoos we would have the actual mark of the beast that could completely control our buying and selling. But we would still need the other component - the beast system, a world empire.
The beast needs to be a worldwide government in control of a centralized world banking system with a cashless electronic payment system that is synchronized to our unique IDs implanted to our hands or forheads. The beast also has to be a theocracy of some kind, probably similar to Rome and its Imperial Cult, the worship of Emperors as gods.
Rev13:15 clearly states those who don't worship this "Image" of the beast (state religion) will be put to death. This type of state religion was first seen in Babylon (Daniel 3), where King Nebuchanezer created a great golden statue and made everyone bow down when music was played. Daniel's friends refused to bow, so he threw them in a furnace.
This is one of the reasons why the city-state of Vatican is so often identified as the Beast. It is a monarchy as well as a theocracy and pretends to be the leader of all Christendom - an imaginary theocracy of the world. The Pope has visits from many influential people from all over the world - including US Presidents who seem very respectful - almost reverent of him. However, I'm not aware of the Pope ordering the killing non-catholics worldwide. (But it was not uncommon during the middle-ages. Christians were killed as well under the guise of Heresy.)
Islam could fit in this group as well - during the Ottoman Turkish empire Islam conquered almost all of Europe. Iran is one such state that has religion mixed with politics. While Islam tends to present itself as a religion of peace, some radical groups clearly have a different vision of Islam. Instituting sharia law worldwide has a tremendeous potential for catastrophe since many Christians would outright reject it and fight against it. This seems like a far-fetched notion but for the last couple of decades Islam has steadily made progress against Christianity as the world's largest religion. Population of Christians has been in decline while Moslem population is booming. Its possible that we see Islam rise as the dominant religion with the highest number of followers in the world. Problem with Islam is its organization. Since the Ottoman Empire fell there has been no supreme Caliphate. ISIS has been trying to establish itself as the new caliphate, but it hasn't recieved recognition outside of the territory it occupied by force.
Israel may be the third candidate. It is a beast in the sense it is a government, but it has the oldest religious system of the group which was at one point a real theocracy - before Saul became King. Israel has a special place as well since it is the only Nation-state that was completely destroyed from the face of the earth and came back from nothing, along with its language, culture and religion intact. It "had the wound by a sword, and did live." Rothschilds already rule the banks of the world, so it may take only a few bribes here and there to transform Israel into the head of the new world order.
Who do you think will lead this future world empire?
Will there be a new religion?
I tend to believe that identifying the image of the beast is more important than identifying the mark. I mean, for believers in Christ. As a warning to believers, it's the image that the world will worship. To avoid idolatry, God's people should know about the image.
It is difficult to pinpoint exactly what it is. I assume it is a form of religion but it could be any belief system that demands unquestioned obedience or worship of something "which had the wound by a sword, and did live". It needs to be something worshiped worldwide and historically religious theocracies seem to be the best fit. Its methods will give it away when it comes - convert or die. The real question is are we willing to die for Jesus or reject him?