What has the Church historically believed about the Antichrist? Early church views are quite interesting!
12th century Antichrist painting
Some, in their inexperience, have ventured to seek out a name [for the Antichrist] which has the erroneous, spurious number [i.e., 616 rather than 666] … In the first place, it is a loss to wander from the truth, and to imagine that something is the case when it is not. In addition, there shall be no light punishment inflicted on those who add or subtract anything from Scripture … Another danger, by no means trifling, shall overtake those who falsely presume they know the name of Antichrist. For if these men assume one [number], when this one shall come having another, they will be easily led away by him. They will not recognize him as the expected one that must be guarded against. (Against Heresies V:XXX:1)