Noahides are non-Jews who accept the seven basic commandments God gave to the world after the Flood. These are belief in God, prohibitions against blasphemy, murder, illicit sexual relations, theft, eating from a living animal and the establishment of courts of law.

Rabbi Henriquez told me: “Almost her entire life, as long as I knew her, my mother believed in God but she was not denominational.

“She loved the Bible, but did not believe in Christian dogma that Jesus was the son of God and the saviour. But she really enjoyed reading Old Testament stories with my sister and I.

“In the final months of her life she was in a hospice where she spoke to a female Christian minister who told her she was part of the Noahide covenant. She became a Noahide at the end of her life. It was a big, pleasant surprise for me.”

While she was alive, Rabbi Henriquez never spoke with his mother about her religious conversion.

He said: “I knew about it, but I didn’t want to be pushy. We talked of mother and son things when she was dying, childhood memories.”

After she died Rabbi Henriquez was wondering what he could do to cherish his mother’s memory.

That was why the Dutch rabbi decided to found Ohel Abraham, the largest Noahide centre outside Israel, in his hometown of Rotterdam.

He said: “I wanted to welcome people like my mother, who believe in God, love the Bible, but cannot connect with Christian theology.

“A lot of people in Rotterdam are interested in Judaism, either because of their former Christian or Jewish backgrounds.

“I started calling and collecting people to see how many I could get together to join me for a study centre. I never thought it would be as big as it is. I had a big group of people who wanted to learn more.”

He explained: “Holland’s Christianity is diverse denominationally.

“There are many free-thinkers. Many people are doubting and leaving the Church, but not leaving God. This is our target audience. Truth-seekers ask questions and don’t get good answers.

“There are very critical people who have usually been to two or three Christian communities before they come to us.

“The final stage is usually messianic Judaism. The intention of Christian missionaries is to lure Jews into Christianity, but they go in the opposite direction. It is often the final stage for Christians moving into Judaism.

“We are successful because there are a number of messianic groups in the area. They become our members and some go on to convert and make aliya.”

The rabbi’s father, Eliezer, came from a Marrano family living in Chile.

Rabbi Henriquez told me: “They had very vague Jewish practices, but no conscious Jewish identity. They would spring clean kitchen utensils, but not keep Pesach.

“They would light candles and not eat certain products, like pork and shellfish. They were not baptised, which in the 1950s was the norm in Chile.”

Eliezer and his brothers asked their mother why they were not Christian. She had no answer. Then Eliezer’s brothers discovered that the family were of Jewish origin.

In the 1970s, Eliezer and his brothers left Chile for economic reasons. Eliezer was the only one to go to Holland.

One of his brothers went to England, another to Denmark, another to Israel. His eldest brother was converted to Judaism by a beth din in Brazil.

On his arrival in Holland, Eliezer contacted the Sephardi community in Amsterdam. The rabbi told him that, according to his family customs, Eliezer was Jewish and just needed to go to the mikva.

But that rabbi died and his successor did not accept Eliezer’s Jewish status. It took Eliezer all of 10 years to be converted by the Amsterdam Ashkenazi beth din.

Meanwhile, Meir’s parents were divorced. He was raised by his mother, but went every week to his father.

He recalls: “I remember that when I was 14 my father started making kiddush and keeping Shabbat. He re-married an Argentine Jew. They later had a Jewish wedding. They didn’t know that the conversion would take 10 years.”

At the age of 25, Meir, who has always worked in a business school, which he now directs, decided to convert to Judaism.

He studied philosophy and religious studies in Rotterdam and Leiden universities, as well as in Haifa and Tel Aviv.

He said: “I researched philosophy, religions and literary science and came to the conclusion that the most viable world system was Judaism. It had the strongest rational argument for its validity.”

Once his father was converted to Judaism, Meir’s conversion was fast-tracked to only two years. He later qualified as a shochet and gained rabbinical ordination eight months ago.

Ohel Abraham, so-named after Abraham’s open tent, to which everyone was welcome, shares premises with Rotterdam’s only Orthodox synagogue, which does not get a minyan for Shabbat mincha when the Noahides meet.

Noahides are not encouraged to perform Jewish religious observance, but they are encouraged to learn about Judaism from the Bible and commentaries. What they do afterwards is left to individual wishes.

Rabbi Henriquez said: “People tend to be inspired by the rules of kashrut. They don’t eat pork or shellfish, but it doesn’t mean they eat kosher meat.”

On Shabbat afternoons, the Noahides recite their own mincha Amidah in Dutch, in which references to the patriarchs and Temple offerings are omitted. Men and women sit separately and congregants face Jerusalem when they pray.

The service is followed by a dvar Torah and a l’chaim.

Rabbi Henriquez said: “There is a lot of singing. It is very important to always involve the heart, especially as our visitors have mostly come from churches where they are used to singing.”

Every Ohel Abraham event opens with the singing of Hine Ma Tov, which means How good and pleasant it is for brothers to dwell together.

“That is very appropriate for our visitors,” Rabbi Henriquez said. “After mincha we always sing Oseh Shalom, He who makes peace, and during the l’chaim we sing songs like Hoshea Et Amecha, Am Yisrael Chai and Adon Olam.”

Four years ago, Dutch Chief Rabbi Chief Rabbi Binyomin Jacobs opposed the Noahide initiative. But Rabbi Henriquez said that Rabbi Jacobs’ son-in-law, Rabbi Moshe Stiefel, has now copied their initiative.

Rabbis Jacobs and Stiefel are both Chabad, who have a slightly different approach to Noahides than Ohel Abraham, which is affiliated with the Jerusalem-based Brit Olam Noahide World Centre.

Rabbi Henriquez would like to see every Orthodox shul make “physical and spiritual space for Noahides”.

He said: “It is very important because we are commanded to be a light to the nations.”

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