We Christians seem to find it quite easy to get offended. Remember the huge campaign against Jerry Springer The Opera? We get offended by Richard Dawkins' every tweet (often missing the point that many of his communications are designed to elicit just that response). How about the absurd faux-outrage over Stabucks' plain red cups? Yep, we're good at being offended.

In wider society, the concept of offence is becoming more and more common. Again and again, and especially on university campuses, the possibility that one group of people might be offended by another group of people's opinions is being used to stifle free speech...

Well over ten years after I left university there are some lectures that remain fresh in my mind. Probably aware that many of his students were half-awake when they arrived, my American History tutor would begin every lecture with a piece of music.

On the day we were studying the Bill of Rights, he pressed play on the ghetto blaster (I know, I know) and out came the sound of The Clash. The song, Know Your Rights, is a stinging satire on how rights enshrined in laws or constitutions can be overridden by those in power. "You have the right to free speech," sings Joe Strummer, "as long as you're not dumb enough to actually try it!"

Sadly, in the UK (and the US), this song is more apposite than ever. Corporations and governments using tools such as the Lobbying Act to stifle criticism. Writers from across the political spectrum are now highlighting another worrying drift towards authoritarianism.

Universities, which are supposed to be bastions of freedom of expression, are at the vanguard of a chilling descent into a post-free speech world.

This was brought into sharp focus this week when the veteran gay rights campaigner Peter Tatchell was 'no-platformed' by a representative of the National Union of Students, accusing him of "racism" and "transphobia." Tatchell has been not only a redoubtable campaigner for LGBT rights around the world for decades, but he has also championed the freedom of speech of Christians and others with whom he profoundly disagrees.

He has defended the rights of Christians to say things which deeply offend him as a gay man – because he realises that freedom of speech is the 'canary in the coal mine' of a free society. When freedom of speech is systematically threatened, we have got a real problem.

It's not an isolated case by any means. Political journalist Ian Dunt has catalogued just a few of the many attempts to stifle free speech in recent months: "Oxford University cancelled a debate on abortion because protesters objected to the fact it was being held between two men; the Cambridge Union was asked (but refused) to withdraw its speaking invitation to Germaine Greer because of her views on transgender issues; officials at London Southbank took down a "flying spaghetti monster" poster because it might cause religious offence; UCL banned the Nietzsche Club after it put up posters saying "equality is a false God", and Dundee banned the Society for the Protection of Unborn Children from their freshers' fair."

Let's be clear what's going on. A calamitous error is being made. People who are calling for bans on free expression have mistaken the airing of views which they find offensive or abhorrent as some kind of endorsement of those views by the university. This is clearly nonsense. But it's sinister nonsense.

It implies that only the views tolerated by a certain clique in charge of discerning who is to be allowed a 'platform' are the views that will prevail. This is the beginning of totalitarianism. If we want to live in a society where we are free to express ourselves and the government and big corporations cannot imprison us simply for our views, then those views have to be allowed to be aired – even if they cause offence.

Offence has become the metric by which some university students define whether a view should be heard or not. This doubtless comes from good intentions – not wanting those who've suffered racisim, sexual assault or other persecution to be forced to re-live their ordeals. We have to take this concern seriously – and gratuitous offence should never be encouraged. However, there is no right not to be offended. As the atheist author Phillip Pullman said when told by a Christian that his book was offensive, "No one has the right to live without being shocked. No one has the right to spend their life without being offended."

When it comes to freedom of speech, we have to draw the line somewhere, though. That line for me is when advocating violence. That's why I'm comfortable with rape advocates, suicide bombing enthusiasts and far right extremists being denied a platform, and even banned from the UK altogether. There is no way people who directly threaten safety or even lives should be welcome on our shores.

However, beyond those constraints, people must be allowed to air their views, or we're heading for big trouble. Without the freedom to express our ideas, even if they are offensive, the freedom we claim we have is meaningless. Does this mean we should support the work of the anti-religious trolls of Charlie Hebdo? What about those publishers who've sought to reproduce images of Mohammed? Of course not. We shouldn't encourage behaviour which is going to cause hurt and pain. But should we ban these things? I'm afraid not.

Christians should care about this topic deeply – not least because our sisters and brothers in many places around the world are systematically denied freedom of speech and religion. In places like North Korea, Pakistan and Eritrea, they are facing real persecution and real risk to their lives. However, here in the West, we don't face persecution – and maybe it's time for us to develop thicker skins and realise that from time to time, we're going to be offended, and that's the price we pay for living in a free society.

If someone says something offensive about us, or our faith, let's not seek to curtail freedom of speech. That's the tip of an iceberg we really don't want to see the rest of... Instead, let's seek a mature debate around the issues we care about – let's live up to our calling as citizens in a free society, rather than dwelling on the offence.

In Galatians 5, Paul talks about the "offence of the cross." The Gospel we proclaim as Christians will, at times, be offensive. While we should never seek to offend and while the Gospel is also comforting Good News, we can never rid it of its power to offend. In this context, Christians must defend the right to speak freely and openly – even if those doing the speaking are offending us! Free speech is a two way street.

George Orwell said, "At any given moment there is an orthodoxy, a body of ideas which it is assumed all right-thinking people will accept without question... Anyone who challenges the prevailing orthodoxy finds himself silenced with surprising effectiveness. A genuinely unfashionable opinion is almost never given a fair hearing, either in the popular press or in the highbrow periodicals." As ever, Orwell's foresight is remarkable. This is the risk we now face.

As well as maintaining a truly free society, there's another advantage to preventing a small cabal of thinkers deciding what is and isn't acceptable to talk about. The oxygen of publicity often helps to destroy the arguments of bigots and crackpots of all kinds.

When fascist Nick Griffin appeared on BBC Question Time in 2009, protestors lined up outside. I wrote this about Griffin at the time, "He's a repugnant human being with toxic views that will wreck this country if he ever gets a chance to put them into practice. But how do I know this? Because he's been given enough rope by TV documentaries and other media outlets to hang himself. If the only thing I knew of the BNP was their party political broadcasts I might think they were reasonable. So while I think a protest is a good idea, a protest which calls for the BBC not to have him on TV is nonsense. The demonstrators' line should be: "we may not like what you say, but in the sort of society we want to live in, you're allowed to say it."

Since that broadcast (and as a result of lots of dedicated local campaigning) Nick Griffin lost his seat in the European Parliament, The British National Party has folded and he has become a footnote in history. Because he was given free speech? Not entirely – but I suspect it played a role in his catastrophic fall in popularity.

As Heather Tomlinson wrote for Christian Today earlier this week we seem to be entering a worrying new period where people are being condemned for what they believe, rather than what they do. As Christians, we need to play our part in building a culture where robust disagreement can be managed well – and offence is rare, but tolerable. The alternative – a society without offence to some, but without freedom of speech for many, is a grim prospect indeed.