I still haven't got over my holiday, though I've been back in London for two weeks. Culture shock, that's what I'm suffering from.

There I was in the sunny Algarve for ten days, in the countryside, amid the cork forests and the fragrance of eucalyptus and wild flowers. And, for the whole of that ten days I never clapped eyes on a TV set or heard a radio. More to the point, I did not once hear anyone shout or swear. I saw no baseball caps, nor oiks wearing them. Not a twinge of pop music.

Instead, there was civilised conversation and people with table manners. Nobody stuffing fast food in his mouth. Nobody chewing with his mouth open. Nobody talking about football. No binge drinkers - though most of us spent a good deal of time in the bar.

In the lounge at any time of day you would find someone actually reading a book. Nobody wore jeans or ugly T-shirts with rude writing on. Picnic lunches and afternoon walks among the cork trees. Then joining newly-made friends for a drink before dinner when there would be conversation about cricket or reports exchanged on what we had seen in the countryside on the afternoon walk.

Then, after ten days, hell came back with a rush. We took a taxi to the airport at Faro and were immediately face-to-face with the snarling, scowling oiks in their baseball caps, stuffing themselves noisily with food too disgusting to eat.

English tourists mainly, I'm ashamed to say, heading for a fortnight's clubbing... and whatever... in the zoo resorts on the coast. They treat even their own friends and families as less than human. Shouting and swearing at one another. Everyone in a barely-controlled rage all the time. You feel a fight could break out any minute.

It was the same back here in London. I'd forgotten how nasty English society has become. Really smartly dressed City types with good jobs in the banks and brokers' offices, but behaving like louts and thugs in the pubs. Every other word f******. In fact the word f****** used as if it were an ordinary adjective like "green" or "pleasant".

I'm not merely resentful because I've come back from holiday. I like my work. I love our friends at church and in the livery companies. But I am disgusted and depressed by the decline in public life and the horrific behaviour you meet in the streets and the pubs every day.

What has happened to us? It wasn't always like this. There were always a few yobs of course, but generally you could count on standards of politeness and good manners.

Last Saturday, I had one glorious day which reminded me of the holiday. I went to Lord's for the Test Match. You form an orderly queue at about eight in the morning and gentlemen in blazers and ladies in summer dresses smile and start up conversations. Everybody seems to be drinking champagne, beer or Pimms all the day long. But there's no swearing and no threatening behaviour.

Then back to the City and the sullen, loutish, shambles. What a falling off there has been. O City, City! Is it nothing to all ye that pass by?

* Peter Mullen is Rector of St Michael's, Cornhill, in the City of London, and Chaplain to the Stock Exchange.