If anyone addressed Leslie Hardman as “rabbi” they were sure to hear about it — from Hardman himself. He always styled himself “the Rev”. He was an Orthodox Jewish minister of what is now a very old school, learned, cultured and tolerant.

He did have a rabbinical ordination, but the title of “Rev”, which has now gone completely out of fashion, somehow suited him better. And he had one qualification to use it that was unique: he was the British Army chaplain who went in with the troops who liberated the infamous Bergen-Belsen concentration camp in 1945.

Hardman was 32 at the time, and it was an experience that moulded his life for ever after. For 60 years after driving into the camp reeking of the thousands of emaciated dead bodies — and the barely alive — around him, he suffered nightmares which he never learnt to shake off.

He was minister (another title now gone into abeyance) for 35 years of one of London’s leading Jewish congregations, one of the most popular men to occupy a pulpit in the capital. But it was his own experience of the Holocaust that made him a public figure, both within his community and outside it.

When BBC television produced a special, The Relief of Belsen, in 2007, his part was played by an actor. Hardman never saw the programme but he was glad that there was emphasis on the suffering of the inmates. “One member of my congregation complained that I was seen in it without a kippar \. Can you imagine that? There I was, burying thousands of bodies, and all this man cared about was that I wasn’t wearing a hat.”

That statement alone indicated how different he was from the Orthodox colleagues who followed him.

Leslie Hardman was born in Glynneath, South Wales, in 1913 into one of the dozens of immigrant families who went to live in the valleys and worked as small traders. He was a small boy when the family moved to Liverpool, where he attended — he always spoke about it proudly as though he were recalling days at Eton or Harrow — the Hope Street Jewish School. It was round the corner, he liked to say, to Hardman Street. “No connection to my family,” he would insist.

He attended a yeshivah or religious seminary and then Leeds University, where he took his BA and then MA. He married in 1936, two years after becoming minister of the Jewish community at St Anne’s, where he was also the ritual slaughterer. From there he took a ministerial appointment in Leeds.

In 1942 he joined the Army as a chaplain. It was on April 15, 1945, that the formative event of his life occurred. He later described how he was told to report to the colonel. He said: “We have uncovered a concentration camp. It is horrible, ghastly, sickening. Most of the inmates are your people. You should go there now. They need you.”

As Hardman said, he had never felt more needed in his life. He immediately set about trying to bring comfort to the survivors and then saying the memorial prayer, the Kaddish, over the dead as he tried to persuade the bulldozer drivers who were thrusting the bodies into a pit to bury them with some kind of dignity.

The amazing thing, he recalled, was the effect his uniform had on the inmates. “They saw the Star of David on my cap and my tunic and they at first couldn’t understand it. Then, they regarded me as a kind of messiah.”

One woman who was so emaciated that he at first found it difficult to be with her, begged him not to leave her. He recalled that he spent an hour talking to her in Yiddish before conducting prayers, the first they had heard for years.