By Paul Harris
I encountered him quite by chance, praying intently at the grave of a famous rabbi.
His eyes betrayed a certain sadness but at the same time, a palpable serenity.
He was, I discovered, the Rabbi of Tunis, Binyomin Hattab, and he was davening at the grave of Rabbi Chai Taieb whose 182nd yahrzeit was that day.
Rabbi Taieb, whose gravestone includes the inscription "Lo met" (who did not die) after his name, is attributed with a number of miracles.
The unusual words were added by the stonemason responsible for the tomb who had originally written "met" (died).
Rabbi Taieb came to him in a dream and wanted to choke him to death, shouting: "Don't you know the statement by the sages, that after righteous people die they are still described as being alive?
"When you wake up in the morning, go to the stone and add the word 'lo' (did not die), do you hear me? The man was very frightened, and did as he was bidden."
But it is not the memory of Rabbi Taieb that haunts Rabbi Hattab and whose quietly spoken but emphatic words reduced my Muslim guide to tears.
Rabbi Hattab's 21-year-old son, Yoav, was one of four Jews killed in January, 2015 by Amedy Coulibaly at Paris's Hyper Cacher supermarket as he tried to disarm the gunman.
Shortly afterwards, Rabbi Hattab told French president Francois Hollande during a private meeting: "I am so sorry, because I thought bad things would happen in Tunis but not here."
President Hollande responded: "It could happen anywhere."
Yoav, who had been studying international business and marketing, was buried in Jerusalem.
But it was Rabbi Hattab's comments that followed that so affected my guide.
Observing that he had turned down the opportunity to take a synagogue post in Paris, Rabbi Hattab said: "Tunisia is peaceful and you can enjoy life here in Tunis.
"People are very friendly and peaceful. I can recommend Tunisia as a destination."
Bearing in mind that my guide was Mounira Derbel Ben Cherifa, director of the Tunisian National Tourist Office in London, and that Israel had recommended that none of its citizens travel for last weekend's annual Lag b'Omer pilgrimage to the island of Djerba, while Britain had advised essential travel only, this was a PR person's dream.
"Coming from me, that should convince Jewish tourists and everyone else," observed Rabbi Hattab.
"Even with the lack of security and what has happened in the past few years, not one Jewish person has been hurt or transgressed.
"Just look at Paris, where a terror attack affects Jews, Christians, Muslims and everyone else."
He was even more emphatic about Tunisia where his family has lived for 2,000 years: "Even after the revolution here, nothing bad happened to Jews.
"There is not much problem with antisemitism."
Minutes before being fatally shot, Rabbi Hattab's son, Yoav, told a fellow hostage that, should anything happen, he wanted to be buried in Israel.
" I wanted to bury him in Tunis," he said. "I wanted him to be close to me. I wanted to be able to visit him every day. It would have comforted me."
Some 50 Israelis were among the 3,000 participating in the pilgrimage this year. Two-thirds were from abroad, mainly from Paris. Tunisian Jewry today numbers 2,000, 400 of whom live in Tunis, with the remainder mainly on Djerba.
This is a far cry from the outbreak of the Second World War when 90,000 Jews lived in Tunisia.
Jews and Muslims have always enjoyed a unique brotherhood in the North African country, living and trading peaceably side-by-side, in a model of harmony never witnessed on this level elsewhere.
Dr Gabriel Kabla left his native Djerba for Paris, aged 19, in 1976, but returns for the Ghriba festival as often as possible, accompanying journalists and other guests.
The Ghriba, he says, is important because it can make all the difference - "the fact that a Muslim country could invite all these people, it's something special when the whole world doesn't want peace between Jews and Muslims".
Dr Kabla, among others, would love to see more Jews participating from around the world, particularly Ashkenazim.
The Jews of Tunisia are not Sephardi, as many wrongly believe, but follow a typically North African or Arab liturgy which, to outsiders, sounds alien. They are actually Ashkenazim.
The liturgy is Tunisian minhag (custom) and unique to the country, although similar to the service in Teheran where there were once 25,000 Jews.
Dr Kabla believes that if Tunisia made it simpler for Israelis to visit the country, far more than 50 would attend the Ghriba.
At present, the option is either to obtain a visa from the Tunisian consulate in Ramallah and then transit through Jordan or Turkey, or apply via the Tunisian embassy in Paris.
He believes that there are 300,000 Tunisian Jews living in Israel and 150,000 in France.
He feels that the Ghriba is never sufficiently well publicised.
"What happens in Djerba the whole year, but especially the Ghriba, offers hope that all Muslims and Jews can communicate peacefully," he said.
"After the Ghriba, everyone can see that communication between Jews and Muslims and Christians and Buddhists, whatever, should be possible.
"There is a special understanding in Tunisia between Jew and Muslim not to love each other but just to communicate and understand each other.
"It's unique because we can't erase 2,500 years of history. Even if we blow out one candle, you can't blow out all the candles at once.
"Djerba Jews decided to stay in Djerba [after 1967 and further periods of aliya].
"They could have left. If they had gone to Israel or France probably they might have had a better life, but they didn't want to. They feel rooted in Tunisia.
"If I decide to retire I would spend more time in Djerba than in Paris."
The Ghriba pilgrimage at its height attracted 12,000 and this year's total was 1,000 more than last year after Tunisia was still reeling from a series of jihadist attacks.
It was a suicide bomb at the Ghriba Synagogue just before the 2002 pilgrimage, killing 21 people, that began the downward spiral.
There has been a synagogue on the site in the Jewish village of Hara Seghira since 586 BCE when Jews fled Jerusalem after the destruction of the Second Temple.
Stones from the Temple are reputed to be incorporated into the walls of the present magnificent 20th century structure, one of 10 synagogues remaining on Djerba.
During the annual pilgrimage, visitors can rent very basic rooms with stone beds surrounding the courtyard, where an auction of scarves takes place.
They are hung on a menara on wheels which is pushed to the other ancient Jewish village of Hara Kebira a few kilometres away. The highest bidder leads the menara.
This year, among the tightest security ever seen, the procession did not complete the full route, turning back after a symbolic distance.
Women write messages of supplication on hard-boiled eggs and climb down to place them beneath the walls of the Ghriba Synagogue. They pray for fertility among other requests.
Muslim women were also happily writing their own please and those looking after the site welcomed them, as usual, as much as their own.
Heavily armed police and military, many with faces covered in balaclavas, ensured that the proceedings went ahead smoothly.
Muslims and Jews mingled joyfully to the sound of Arabic music, familiar to both, and Jewish women - albeit fewer than in previous years - donned traditional Djerbian dress in identical style to their Muslim sisters.
Israeli Aziz Baroum made the pilgrimage with three friends despite his government's warning.
"Each year they say the same thing but personally I feel at home here, the welcome is excellent and the people are warm," he said.
Djerbian René Trabelsi, one of the organisers, said: "I think all these pilgrims who have agreed to come in spite of restrictions imposed on travelling to Tunisia by some countries, are very brave and they have shown their love to Tunisia and Tunisia appreciates them."
Tunisian Hassan Chalghoumi, now living in France, said that the pilgrimage sends a "message of hope and peace".
"There are moments in Europe when we doubt, and ask, can we live together or not?" he asked
"For example, there are 1,500 Jews living in Djerba. There are many communities that live together and that is a universal message. It's a message of peace".
Tunisian Prime Minister Youssef Chahed and Tourism Minister Sella Elloumi were on Djerba for the pilgrimage, as was American ambassador to Tunisia, Daniel Rubinstein, who lit a candle.
Chahed said he had "a double message. "Firstly, Tunisia is a country several thousand years old, with a deep-rooted history of openness to all religions. Secondly, security has come back to Tunisia".
Elloumi told me: "Tunisian Jews and Muslims have the same origins and religion has no impact on their relations. It's unique. There are 3,000 years of history and three religions in Tunisia."
* Paul Harris travelled as the guest of the Tunisian National Tourist Office - www.discovertunisia.uk
* Tunisair flies from Gatwick and Heathrow
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* The Bloc Gatwick Hotel is literally within South Terminal on Level 3. Great accommodation with everything touch-controlled at bedside and wet rooms. There's even complimentary water and free wifi. Tel 0203 0510 101 or visit www.blochotels.com