The Swedish dissident pastor Fredrik Sidenvall’s paper on “Confessing the Faith in an Anti-Christian Culture,” which was delivered on his behalf at the recent Congress on the Lutheran Confessions in Minneapolis offered a fascinating Biblical and Confessional study of what is meant by “Antichrist.”
In Lutheran usage, it is not some political figure who seizes power before the last days, such as End Times enthusiasts are always trying to identify. Though the last days will indeed involve the reign of an antichrist, there are actually many of them throughout history, as the Epistle of John indicates, and they arise WITHIN the Church.
They also have different marks. An antichrist will be a “man of lawlessness”; he will be a “destroyer of truth”; and he will offer a “new gospel.”
I would add that St. John says that the antichrist will deny that Jesus has come in the flesh. To my knowledge, popes have not done that. But liberal theologians–the neo-gnostics, those who distinguish between the “Christ event” and the historical Jesus, and the rationalists who reject the Incarnation–do make that very denial.