When my children first discovered swear words, my husband and I set up some rules at home.
Swear words, we said, were strictly forbidden and also words that came into a kind of second category - things like 'Shut up!' or 'You idiot' - which we used to call 'Things that are Not A Very Nice Thing To Say.'
One day I was driving with my six year old son William and he suddenly said, 'Mummy, is Birmingham a swear word?'
'No, of course not,' I said.
He hesitated for a moment and then he replied, 'OK. But it's Not A Very Nice Thing To Say, is it?'
Well, I'm not sure what was going on his school playground - whether kids were going around saying 'Oh Birmingham!' whenever they dropped their packed lunches. But it made me laugh.
Having said that, I've come to see - over the years - that swearing is really not something to laugh about at all.
In fact, it's a very violent and damaging thing.
Which makes it sound as though I am some kind of saint who never swears. Which I'm not. But I have managed to cut it down to no more than once a week - when I check my phone for the latest Arsenal score.
Back in the day, however, it was a different story.
In the 80s and 90s I worked in an investment bank and swearing was the absolute norm - to which I made no effort whatsoever to counter. In fact I prided myself on being able to swear as outrageously and colourfully as any of my colleagues.
But a few years later, when I started a spiritual journey, when I allowed God into my life, I began to hear a voice telling me that the swearing had to stop.
But why? Why did it have to stop?
I mean, it's only words - isn't it?
I know, of course, that the Ten Commandments say do not take the name of God in vain - but where's the harm in giving vent to the occasional outburst of effing and blinding?
It wasn't really until the other day when I read about an extraordinary primary school experiment that things began to come clear.
In this experiment the teacher got the children in her class to bring in some jam jars. Then they did that thing where you put a cylinder of soggy blotting paper into the jar and squeeze a bean down the side. The idea is to examine how the bean grows, how it puts down its roots and then puts up a little shoot.
This was exactly that same old tried and tested experiment - but with a difference.
The difference was that this time the teacher asked half the pupils to go home and to be kind to their beans. And the other half to be mean to their beans.
The kind group were to say things like 'I love you bean.' 'You are a wonderful bean.' 'Grow, little bean.' 'Be a big strong beautiful bean.'
The mean group were told to say things like 'I hate you horrid bean.' 'You are a miserable bean.' 'Shrivel up, bean.' 'I hope you stay a tiny pathetic ugly bean.'
So what do you think happened?
Well, truly, a few weeks later the children brought in their beans and the ones that had received the kind words had flourished, while the ones who had been berated with mean words had barely grown at all.
Worse than that, the children who'd said the kind things felt good and happy; and the children who'd said the mean things felt bad and miserable.
When we swear and say bad things, we don't just cause injury and hurt to the people our words are directed at. We cause injury and hurt to ourselves. The negative act itself diminishes us.
As I read about the bean experiment, I began to see that swearing is not only bad but also bad for us.
It's like swearing is actually the very opposite of praying.
Whereas praying is seeking blessing for others and the world around us, swearing is seeking curses on others and the world around us.
Not surprising, perhaps, when you think that the word cursing is synonymous with the word swearing.
So, ask yourself - would you like to be in an environment where curses are being flung about the place all the time?
In that case, stop swearing. Give it up.
And see what happens next.
Do you start to feel more at peace? Do you feel bigger and stronger and healthier than when this poison was constantly welling up inside you and spewing out all over the place.
But what, I hear you ask, should I do when I find feelings of anger and frustration building up inside me? Surely it's not good to bottle them up?
No, of course, it's not good. And that's where God comes in. God says give all your anger and frustration to me. I can take it. Let it go. Get it out. Put it on me.
Don't take it out on your neighbour. Don't take it out on yourself.
Love your neighbour. Love yourself. Even love your enemy.
Don't curse anyone. Let me be the one to judge.
And, as you for you - be free.
Free from swearing, free from being a source of cursing, free from hurting others - and free from hurting yourself.