Don’t let anyone deceive you in any way, for that day will not come until the rebellion occurs and the man of lawlessness is revealed, the man doomed to destruction (2 Thessalonians 2:3).
There have been a lot of theories as to who this "man of lawlessness" is, from the Pope, to one of the Roman emperors in the first century, to the "Antichrist." It is this latter identification that seems to be in vogue today. One of those that I respect for careful biblical exegesis is a man named John MacArthur. Here is his exposition of the passage and explanation of the man of lawlessness. It is quite long, and I only perused it myself, but I link to it here for your consideration. You can either read it or hear it here:
http://www.gty.org/resources/sermons/53-7/the-coming-man-of-sin-part-1
http://www.gty.org/resources/sermons/53-8/the-coming-man-of-sin-part-2
http://www.gty.org/resources/sermons/53-9/the-coming-man-of-sin-part-3
http://www.gty.org/resources/sermons/53-10/the-coming-man-of-sin-part-4
http://www.gty.org/resources/sermons/53-11/the-coming-man-of-sin-part-5
http://www.gty.org/resources/sermons/53-12/the-coming-man-of-sin-part-6