In fact, he spends every morning learning and teaching in a yeshiva in the Jerusalem religious area of Kiryat Sanz.

But in his afternoons, dressed in the same traditional black garb, he advises top international companies like Google on business strategies.

So how did this New York-born yeshiva bocher, who now writes a weekly business column for the Jerusalem Post, end up having his technological inventions being featured on the Massachusetts Institute of Technology and FINAT websites and being voted one of Inc Magazine's top financial entrepreneurs of the year?

Part of the answer, says Rabbi Ginzberg, lies in his genes.

He is descended from a rabbinic family. His great grandfather was a rabbi in Romania and his grandfather was a rabbi in Minneapolis, Minnesota.

His father, Rabbi Sholom Ginzberg, heads a girls' seminary in Brooklyn, New York.

Issamar says: "I have zechut avot (merit of the fathers) and no doubt that helps."

But it is not just his well-honed yiddishe kop (Jewish brain), inherited from generations of Torah scholars, which has led to his outstanding success but also the fact that both his parents were innovators.

His father created the first Hebrew font for Macintosh computers.

Rabbi Ginzberg junior said: "He had no Hebrew on his computer so he created it."

Issamar continued: "When they see something, brilliant entrepreneurs ask, 'Why not me?' That's what my father did and that's what I do."

His mother Chaya Ginzberg, who teaches at seminaries and schools, wrote Road Signs for Success, modelled on the Highway Code, on how to make relationships work and devised the game CheckMate which helps singles in their quest for suitable partners.

Certainly an innovative and empowering family!

Although Issachar went through the traditional charedi educational system, leaving school for yeshiva after his barmitzvah, his grandfather, who was born into a Romanian Yiddish-only speaking community which had never heard of Hitler when the Nazis invaded, was insistent that his family be acquainted with the ways of the world.

Issamar said: "I had the minimum of secular education from school, but I had a tremendous amount of self-education as well as from my parents."

In fact, Issamar claims that he learned a lot of his English from computers, which he started using at the age of four.

He said: "I learned how to read English from the computer as a child. I learned words like 'save', 'quit' and 'revert' from it."

By his teenage years, Issamar was already earning money by creating computer icons.

He recalls: "There was no such thing as personal icons. Graphics were very primitive then.

"I came across a programme for an icon and was fascinated as to how it could be done. I learned how to do it. I created computer icons. I gave people the ability to express their individuality with icons of their choice."

At 14, in his evenings after yeshiva study, Issamar would provide shareware icons for free and offer another 100 for $10.

Rabbi Ginzberg said: "I started getting cheques when I was in summer camp. I used to sit with my mum at the kitchen table and address envelopes and mail out software to people who sent me money from around the world.

"One of the people who bought my icons bought out Apple computers, so I got a cheque from Apple computers.

"My collection of icons was featured on the famous computer website FINAT. It was their No 1 product for several weeks in a row.

"There were thousands of downloads which led to many, many cheques. My icons were also featured on the Massachusetts Institute of Technology website."

Teenager Issamar had learned the power of software, the Internet, sales and marketing.

After helping the proprietor of a clothing company design a brand and logo for a new line of shirts, Issamar's fame spread quickly.

At 15, he began to get calls for business advice from many people.

Issamar said: "People asked me how to increase their business or how to fire somebody without making them feel bad. I gave advice on how to generate new clients and make more money.

"People found someone they could trust who is a good sounding board."

On his marriage, Issamar and his wife Esther settled in the yeshiva town of Lakewood, New Jersey.

He recalls: "When I came to Lakewood I was in mortgages. That led to real estate and to lots of high-level connections.

"I started advising people on building businesses.

"I was a member of a website on how to build credit. One of my mantras is that whatever you do you have to figure out how to make money out of it.

"I hired a guy for $50 to write a computer programme that would go into the website and extract anything I wrote.

"I had pages and pages of valuable information which I had written over a long period of time on how to build a business. It eventually became the book Business Credit Secrets."

Now he has branched out into marketing eight-hour CDs on business advice.

While in Lakewood, Rabbi Ginzberg was voted one of Inc Magazine's top financial entrepreneurs of the year.

Four years ago, he and his family went to Israel for a three-month vacation and have stayed ever since. He learns Torah in the mornings and moonlights in the afternoons as an internationally acclaimed business consultant and entrepreneur.

He said: "My first goal is to make a living. In a year or so I want to open my own synagogue, which would be self-supporting.

"My second goal is to help as many as possible."

For this purpose, Rabbi Ginzberg gives his services free to large business seminars. After addressing the Israeli Translation Association, he was recommended to speak to Google on Behind the Curtain of Social Media.

Rabbi Ginzberg said: "It was not the usual run-of-the-mill stuff. Many people think they can make money on social media like Twitter, Facebook and LinkedIn.

"They get disappointed, wasting lots of hours not making money.

"I explained that money really is there and that you can use it for your professional advancement."

So what reaction is there in these top business seminars to being addressed by a charedi rabbi in a frock coat?

Rabbi Ginzberg says: "For many clients I am their first exposure to an Orthodox Jew and for others I am the first not preaching religion to them.

"When they see a picture of a rabbi above a newspaper column, they assume it is about Torah.

"But mine is in the Tuesday business section of the Jerusalem Post. As my reputation spreads, people don't care what I wear."

Rabbi Ginzberg is due to visit Manchester next week on his first trip to advise business clients in the UK.