Jerusalem Compass shows many arks face the wrong way

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Tests with a unique compass in recent months have established that many of the world’s — and even Israel’s — synagogues have been built without their holy arks facing the Temple Mount in Jerusalem, even though this is the traditional position for Jewish prayer.

The synagogues have been tested by the world’s first and only “Jerusalem Compass,” a mechanical solid brass device that points to Jerusalem and the site of the Temple from anywhere on Earth. The compass was invented by a New Jersey-born Jerusalem yeshiva student who goes only by the name “Moshe.”

The Shulchan Aruch, the Jewish legal code compiled by Sephardic sage Rabbi Joseph Caro in the 16th century, states that a praying Jew should face the land of Israel, and that if they are already in Israel, they should face the site of the destroyed Temple and the Holy of Holies in Jerusalem.

Moshe found that many synagogues in the diaspora have been built with their holy ark (Aron Hakodesh), which houses the Torah scrolls, facing the “wrong” direction — either because the builders did not know where Jerusalem was in relation to its location or because of building ordinance constraints.

“Most diaspora Jews face the traditional mizrach [east] when they pray, but if you face east and pray in Florida, Toronto or London, you will be facing totally different spots,” Moshe noted.

Even in Israel, and Jerusalem, many are significantly off the mark. The synagogue at a well-known haredi yeshiva in the capital, for instance, faces north rather than toward the Temple Mount.

Conventional compasses always point north because of the magnetic force of the North Pole, but since Jerusalem is always in a different direction depending on where you are, the Jerusalem Compass has a “magnetic polarity recalibrator” to point to the right direction.

The $25, non-electrical, non-computerized device is pre-calibrated for the continental United States, but can be recalibrated to virtually any other location on the globe.

Moshe, who moved to Israel two decades ago and lives in Jerusalem’s haredi Har Nof neighborhood, said he first thought of the need for such a compass when he was studying the Talmud tractate of Sukkot in a yeshiva in 1991.

“I thought to myself how it would be possible always to find where the Holy of Holies of the Temple stood,” he said. “I quickly came up with the concept, but it took me almost 14 years to turn my ideas into an actual product.”

After he designed it, the inventor went to China to have it manufactured according to his exact specifications. Within a few months he had created the compass, as well as a keychain attachment, a gift box and instructions, with endorsements from prominent haredi rabbis in Jerusalem.

“People I’ve shown it to are very enthusiastic,” Moshe said. “But they are shocked when they find they have been praying for years facing the wrong direction.”

He has teamed up with the Monsey, N.Y.-based company TES, which also sells Jewish software, to market the device by mail (go to

“It fills a real need, and also will be valued for sentimental reasons because it always faces Jerusalem,” said TES Vice President Jeff Milgram.

“I remember recently being in the windowless room that serves as a synagogue at New York’s JFK International Airport. Nobody knew in which direction to pray. I pulled out my compass, and it pointed to Jerusalem. Everybody was amazed. It seemed to defy nature.”