2 Thes. 2:3-7 (ESV)
Let no one deceive you in any way. For that day will not come, unless the rebellion comes first, and the man of lawlessness is revealed, the son of destruction,  who opposes and exalts himself against every so-called god or object of worship, so that he takes his seat in the temple of God, proclaiming himself to be God.  Do you not remember that when I was still with you I told you these things?  And you know what is restraining him now so that he may be revealed in his time.  For the mystery of lawlessness is already at work. Only he who now restrains it will do so until he is out of the way.
This is one of the main texts that people use in trying to find the Anti Christ. To this day we Lutherans believe that the pope fills the office of the anti Christ. It isn’t that we think everything he does is pure evil without any merit. Indeed, I have quite a bit of respect for the current Pope. But his office is one that makes him vicar of Christ on earth, he replaces Christ as leader of the church. (At least in Roman catholic theory). Now others might point to the “prophet” of the Lds church. And there I certainly have to say there is a spirit of anti Christ at work. However, the LDS church is one of pseudo Christianity and is therefore outside the church of Christ which is the temple. The Temple is the body of Christ which is made up of believers of Christ who are the Church. This is the paradox here. We Lutherans, for everything we disagree with concerning Rome, still consider it to be a Christian church, within which Christ is heard, and salvation is given. In fact we may be more tempted to believe Catholics are Christian than the Baptist down the street. The other day I was taken to task for not being up on all the current evangelical teachings concerning Mormonism. Problem is I don’t care what they say. They are so wholly skewed themselves they make a very poor choice for determining the correctness of anything. But Catholics I will read, talk to and listen to. At least they still have a couple theologians in their mix. They do teach the trinity, sometimes I wonder if that is taught among evangelicals, which accounts for a lot in their ranks finding almost total agreement with Mormons. They themselves don’t know Christian doctrine! But the Roman Catholic Church is still Christian, and the pope in those ranks claims a great deal of Christ’s authority for himself in that church, and this is why we think that the office of the Papacy is the office of the Anti Christ.