Be Not Deceived

What does it mean to be deceived? Who is the antiChrist? Who is the man of sin? How is what man calls righteousness just the opposite? What exactly is 'secondary doctrine’ and should you be silent when other disagree? What is the 'pre-tribulational rapture theory’ and when did it come about in history and why is that an issue? How do we see that only what God says in His Word matters? How is this a doctrine meant to stir men up and keep them in fear? Why are some believers troubled?