In school. At a football match. In a superhero movie. At the pub. In the supermarket. In an ever-so-slightly edgy pop song. We hear the f-word so often these days that much of the time it simply washes past us. Used not only as a curse or a graphic substitute for 'sex', but also as the Oxford Dictionary puts it, as 'an intensifier', it's got to be one of the most popular words in the English language. We all learn it from a kid in a corner of the playground at about age eight – at the latest – and many of us barely stop using it from that day on.

A few decades back, Christians held a fairly high line on 'bad language'. It probably came from a biblical disdain for blasphemy – a linked area – and that nagging concern that increased swearing indicates the gradual disintegration of Western civilisation. Today though, we've relaxed considerably, perhaps not in our own use of certain words (the Bible does tell us to "not let any unwholesome talk come out of your mouths" [Ephesians 4:9] after all), but in our acceptance of them. "The swearing didn't bother me", is a common response to profanity-filled films and TV shows. There are just more important things to get upset about.

Yet we all shudder the first time we hear our children use the word; even to ask what it means. I think that's because the f-word is much more problematic than we give it credit for – it's not just that its use demonstrates a lack of linguistic imagination.

The problem is rooted, I think, in its origin. You've probably allowed it to roll around your head a few times since you started reading this (be absolved; that's totally my fault), and perhaps you've noticed what a harsh, unfriendly word it is. When you trace it back through the ages, you discover that it seems to have two distinct roots of meaning. One is sexual – referring to the act of intercourse – but the other is more troubling. A lot of the words from around the world which linguists think feed in to our modern f-word don't refer to sex, but violence. These words are defined "to hit", or "to strike". The etymology eventually tracks back to the Latin root Pugnus; the same word that takes us to fighting, punching and fist.

So when we use the modern form  we're using a word which encapsulates both sex and violence. To make love AND to strike. All wrapped up together.

I don't think Christians should be upset about the f-word because it marks some sort of moral decline. I think we should be upset about it because it's casual misogyny (another root meaning is 'penis'), which takes the beauty, intimacy and love of the sexual act and corrupts it. We're probably all still agreed on the ugliness of violence. As Christians, we probably all still agree that in hitting one another, we strike the image of God in another person and marr his image in us. Sex and violence are never things that should be twinned together, yet in this word that's exactly what we find. Are there really so many more important things to get upset about?

I have a nagging feeling that among all the areas in which Christians have relaxed in recent years, this might be one that some of us have got wrong. In assuming we're chilling out about some of the non-essential issues, we've missed something quite important. What does it mean that a word with these meanings – and deep down, I think we have to concede that they ring true – is right there at the heart of our culture? Heard every day, billions of times, all around the world, far more often than words of worship or love. Should we really just be waving it past without critique?

I don't think so. Once you know what the f-word really means, you can't simply give it a free pass on the grounds of avoiding irrelevance. It's not just a holiness issue – although I think that's part of it – but a justice issue too. My hunch is that if more people knew the ugly, violent roots behind the f-word, they might just stop using it so much (and so maybe we should tell them). If the swearing doesn't bother you, maybe it's time that it did.

Martin Saunders is a Contributing Editor for Christian Today and the Deputy CEO of Youthscape. You can follow him on Twitter: @martinsaunders