Unfortunately for him, the right to freedom of speech and expression is only recognized as a human right the same day but 428 years later under Article 19 of the Universal Declaration of Human Rights.
Article 19 ¦¦ Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers.
Martin Luther was known for strongly disputing the fact that freedom from God's judgement and punishment for sin could be traded with money. He had never heard of hedge funds yet...
Today the boss shaved his beard, got a haircut and wears a tie. He publishes no bull anymore but rather bulletins, sells weapons to people that he knows, freindly governments are planning to go to war against, sells weapons to governments that go to war against the one he sold weapons to just before, sells rebuilding, highly acid sparkling beverage and Wrestling TV shows to the new freindly governments after everything has been wrecked and generates huge financial profits by letting all the people work to support monetary institutes instead of having it working the other way around.
You can now very well say:
'Your doctrine is shit!'
'Your industry is shit!'
'Your laws are shit!'
'Your food processing is shit!'
'Your weapons are shit!'
or 'Your economic and monetary systems are shit!'
'Not to my client.' his lawyer will respond politely. The new boss doesn't care what you say or think because what matters only is that everybody owes him money. You could publish teachings à la Luther with millions of theses against him, he would'nt give a dry shit. Thoughts and ideological speeches don't bother him too much as long as everybody keeps buying plasma screens, air-conditionned cars and homes they will only be the legal owner of once they are too old to enjoy true freedom with no interest rate.
Oddly enough, free thoughts like those expressed by Luther and by many other scientists and artists may very well have and did, in many cases, lead to imprisonment or death in centuries past . And now that we're allowed to speak, we just go to work. Isn't it always more exciting to do things when they are prohibited?