My shul in Tel Aviv is a microcosm of Israeli life. Every type of Jew attends and is welcomed.

But for most of the year, I’m one of only two Cohanim. And there’s hardly ever a Levi.

In the summer of last year that changed. We had a new oleh from London. Mike Sinclair, in his mid 70s and a Levi, became a regular on Shabbat.

Having been raised in a secular home, neither he nor his late father knew they were Levi’im until his uncle died and left him the family records. Among them was his grandfather’s ketubah. His grandfather, born in Warsaw, was Yehoshua Zeev ben Zusman, HaLevi. Mike flew to Warsaw, visited the Jewish cemetery and after hours of exploration found the Szulzynger family graves. There was his great-grandfather, Zusman be Yehoshua Zeev Halevi.

The names and dates of his great-grandparents matched the details on his grandfather’s British naturalization papers. The inscription on his great-grandfather’s gravestone spoke of a pious, charitable and learned Jew respected throughout his community.

What had happened to sever the chain? Mike knew he was the only surviving member of the family in the male line. Thus commenced his introduction to Yiddishkeit.

As Mike would describe it, his journey back to Jewish life had many ups and downs, and twists and turns.

But notably, more than 25 years ago, former chief rabbi of Britain, Rabbi Jonathan Sacks started an organization, Jewish Continuity, whose aim was to transform the Jewish community by intensifying education at all levels and ages. He asked Mike to take a leading role in this enterprise. This project was formed without the involvement of the majority of the rabbis of the United Synagogue, the dominant Orthodox body in the United Kingdom.

Dr. Michael Sinclair specialized as a psychiatrist after graduating in medicine at London University. In 1971, he gave up the day-to-day practice of medicine and entered the health-care industry.

For nearly 50 years, he has founded and built companies in the United States, Europe and Australia, that have, against the odds, become market leaders in their chosen fields.

Michael Sinclair

I asked him how he had achieved this surprising result.

He replied: “Whatever success I have had has resulted from working with people who are better than me; seeking constructive criticism; being certain that we can deliver; listening to the customer, always having a mentor; and never being afraid of crazy ideas.

He continued, “I brought these views to the establishment and operation of Jewish Continuity.”

“We started with a small group of highly talented individuals. The Chief Rabbi had posed our community the question: ‘Will we have Jewish grandchildren?’ ” Our task was: “The intensification of Jewish life.”

“But early on, we asked ourselves, how will me measure success?” explained Sinclair. “We identified a number of criteria of success. They included: the majority of Jewish children in full time Jewish schools, over 70 percent of Jewish teenagers going on Israel trips, an increase in travel to Israel, an increase in synagogue affiliation, an increase in the consumption of Kosher foodstuffs, an increase in the sales of Jewish books, an increase in the number of kosher restaurants, an increase in support of Jewish charities and a reversal of the demographic trend—more Jewish marriages and more Jewish children.”

Sinclair added, “We advertised our messages widely directly to the community, both in the Jewish and national media.”

“The strapline was: Today, we’ll lose 10 more Jews.”

This number reflected the daily decline in the U.K. Jewish population since 1950, he said.

The advert ended with a call to arms:

This is the moment of truth. Do we simply stand by and watch the gradual disintegration of the community? Or do we join battle to do more than just survive, but to thrive? We do have a future. Believe that. Let’s fight for it. 

“The rabbis were angry,” said Sinclair. “They felt that they had been excluded.”

“Reform was angry. They saw that our message was going to reach their members directly, and undermine much Reform theology and lifestyles.”

Sinclair blames the conversion and divorce policies of the liberal, Reform and Masorti communities as having been both a causative factor and having exacerbated the communal tragedy in the Jewish world today—that a growing number of people, through no fault of their own, consider themselves to be Jewish, but are not.

“The view that we can pick and choose the ‘brand’ of Judaism that appeals to us, without having being made aware of any negative consequences lies at the root of the issue,” said Sinclair.

Avrohom Shmuel Lewin is a Tel Aviv-based writer and the former press secretary of Israel’s first Science Minister Yuval Neeman.