As JC readers hardly need reminding, early January is not the only time when we give up, cast off, make changes.

My summer holidays often fill me with similar zeal: a week of sipping pastis and eating grilled fish, and I often jet back into Stansted with stout plans of living, thenceforth, like a European, never again making do with a chicken tikka slice from the garage.

And my biggest change — I should call it a turning — happened one autumn Monday. Monday 13 October 1986, to be precise.

I grew up in Southport, Merseyside, a day-trip-cum-retirement town, whose pretty synagogue sits tidily behind the railway station.

The entrance is a half dome, supported by pillars, and around it there is (or was) golden writing, in Hebrew, on an Aegean blue background. As a small boy, who was not Jewish, I felt it was connected to ancient Greece. I asked why, because I was interested in almost everything. No-one knew.

By 13 October, 1986, I had lost all curiosity. I was 15, and trapped. Later, in doomed relationships and awful jobs, I never felt as trapped as I did then, aged 15. I hated everyone and everything, save a couple of teachers, a few friends and my imagination.

I survived by casting myself into the films and television shows I admired. I was a heroic POW outwitting the Nazi goons of Colditz.

I was Norman Stanley Fletcher, in Porridge, Hawkeye Pierce in M*A*S*H. I saw myself as prisoner of an absurd system, its custodians obsessed with the length of my hair and the greyness of my socks. Since I couldn’t escape them, my job was to ridicule and irritate them, to the amusement of my fellow inmates.

And what of my parents? Their bright, perpetually curious 11-year-old had trotted off to one of the best schools in the region — at painful expense to themselves (my Mum was a dinnerlady) — and turned into Jonny Rotten.

It was especially hard for my father, who had joined the RAF aged 16, and by his mid-30s realised that no baker’s son could become an officer. He took the only other thing the class-ridden Forces were offering: classes, acquiring qualifications and eventually leaving the RAF to become a language teacher and translator.

Once, teaching conversational German in Walton Prison, he asked a lifer what he’d done on his holidays. In retrospect, it was embarrassing for him, but far more painful for him was his son coming bottom at German, French and everything. “Are you not interested in anything?” he asked me once, tears in his eyes.

Then upon this one October day, in my almost fanatical indifference, I walked home from school, past a synagogue unusually busy for a Monday afternoon.

Amongst those milling about outside, shrouded in tallit, crowned with tfilin were men I saw every day: the chemist, the GP, the optician. The date was Tishri 10, 5747; Yom Kippur.

I’d learnt the statutory minimum about the world’s faiths. I knew of Chanukah with its lights and gelt, the deep-clean of Pesach, about Yom Kippur, the Big Sorry, and once, in primary school I’d been inside the synagogue: glimpsed the bimah and the ner tamid, looking dead as a local museum without worshippers.

Now it was an anthill: people going up and down the steps, pausing to adjust their garb or someone else’s, shake a hand, crack a joke and from within, more like traffic noise than a holy injunction, the blasts of the ram’s horn.
And suddenly it hit me.

That here, just past the technical college (where I’d be resitting my exams, everyone said, if I didn’t change my attitude), past the bedsits known as the bad bedsits (where I was also destined) here was a ritual that was millennia-old, swept in from the Near East across the sand dunes of Southport by waves of history. Why? How? What was going on here?

A switch flicked; indifference was no longer possible. We had many books in our house – and when I’d exhausted them, I spent my Saturdays in the circular, sacred space of Liverpool’s Picton library, moving from Jewish history to that other wandering people, the Romani, and then on to anthropology.

This was teshuvah: the transformation intended to occur in the ten days between Rosh Hashanah and Yom Kippur. Yes, New Year, yes promises; but nothing to do with giving up or turning away.

The hefty studying at home could not fail to affect the learning I was supposed to be doing at school, where my marks crept steadily upwards.

“Matthew, you have turned into a different person!” exclaimed my German teacher.

“No, sir,” I said, remembering the true meaning of teshuvah. “I turned back.”

Matt Baylis is a crime novelist, screenwriter and journalist who spent his formative years watching television