... In complete opposition with all his orthodox commentators, who all expect that his prophecies are still to come off, after more than 1,800 years, “John” never ceases to say, “The time is at hand, all this will happen shortly.” And this is especially the case with the crisis which he predicts, and which he evidently expects to see.
This crisis is the great final fight between God and the “antichrist,” as others have named him. The decisive chapters are XIII and XVII. To leave out all unnecessary ornamentations, “John” sees a beast arising from the sea which has seven heads and ten horns (the horns do not concern us at all) “and I saw one of his heads, as it were, wounded as to death; and his deadly wound was healed.” This beast was to have power over the earth, against God and the lamb for forty-two months (one half of the sacred seven years), and all men were compelled during that time to have the mark of the beast or the number of his name in their right hand, or in their forehead. “Here is wisdom. Let him that bath understanding count the number of the beast; for it is the number of a man, and his number is six hundred three-score and six.”
Irenaeus, in the second century, knew still that by the head which was wounded and healed, the Emperor Nero was meant. He had been the first great persecutor of the Christians. At his death a rumour spread, especially through Achaia and Asia, that he was not dead, but only wounded, and that he would one day reappear and spread terror throughout the world (Tacitus, Ann. VI, 22). At the same time Irenaeus knew another very old reading, which made the number of the name 616, instead of 666 ...
About 300 years before our era the Jews began to use their letters as symbols for numbers. The speculative Rabbis saw in this a new method for mystic interpretation or cabbala. Secret words were expressed by the figure produced by the addition of the numerical values of the letters contained in them. This new science they called gematriah, geometry. Now this science is applied here by our “John.” We have to prove (1) that the number contains the name of a man, and that man is Nero; and (2) that the solution given holds good for the reading 666 as well as for the equally old reading 616. We take Hebrew letters and their values —
ב (nun) n= 50 ק (keph) k = 100
ר (resh) r = 200 פ (samech) s= 60
ן (van) for o = 6 ר (resh) r = 200
נ (nun) n= 50
Neron Kesar, the Emperor Neron, Greek Nêron Kaisar. Now, if instead of the Greek spelling, we transfer the Latin Nero Caesar into Hebrew characters, the nun at the end of Neron disappears, and with it the value of fifty. That brings us to the other old reading of 616, and thus the proof is as perfect as can be desired ...
http://www.marxists.org/archive/marx/works/subject/religion/book-revelations.htm