Many Jews — even some in the Orthodox community — aren’t aware that Jewish law has a great deal to say about money. Yet large segments of the Torah (the Five Books of Moses), as well as the Talmud and the subsequent writings of the sages throughout the generations, are dedicated to discussing the minutiae of laws relating to business, money, loan-taking and making, banking, and other economy-oriented topics.

Orthodox Jews who have a business dispute will often seek the services of a Jewish court of law (Beit Din) to adjudicate their disputes. In the US and elsewhere in the diaspora, as well as in Israel, these courts are considered legal arbitrators. If the parties agree in advance to accept the Jewish court’s decisions, they will be enforced by state-sponsored courts.

But the Keter Institute for Torah Economics has as its goal, according to one of the organization’s heads, Rabbi Shlomo Ishon, the integration of the Jewish approach to money and business in modern Israel — to as great an extent as possible.

The Institute publishes lists of companies and investment funds that do and do not abide by basic laws against taking or paying interest — a Biblical no-no for Jews doing business with other Jews. Those wishing to abide by the laws forbidding receiving interest, for example, are advised not to buy the bonds of several very large Israeli companies, who pay interest but have not filed for a heter isqa – a contract that circumvents the prohibition on interest by “selling” the debt to a Jewish court of law.

Another list includes companies traded on the Tel Aviv Stock Exchange that are and aren’t “Sabbath observant” (according to Jewish law, it is forbidden for a Jew to benefit monetarily from the violations of the Sabbath). Exceptions are made for companies that, while technically violators of the Sabbath, supply services that may be required to save lives (those involved in saving a life are generally exempt from Sabbath observance), are involved in security matters, or have taken “significant steps” to prevent Sabbath violations in their business model.

The Institute also publishes position papers on various issues, discussing in depth the Jewish approach to issues like whether or not doctors are allowed to go on strike, minimum wage, the refugee status of foreign workers and Israel’s obligation (or lack thereof) to provide them with work, the halachic implications of bankruptcy, and whether or not observant Jews are commanded to prefer Israeli-made products (that report was prepared at the request of the Knesset, the organization said), among many others.

And then there is the challenge of converting Biblical monetary values into modern currency values — important not just at Purim time (when the mitzvah of a half-shekel donation is commanded), but for many other business transactions, as well as marriage contracts, where “the value of a penny” (shaveh p’rutah) is the basic unit of value.

The half shekel donation, as described in Exodus 30:11, had a dual purpose in the Bible — as a means of taking a census, and to provide donations for the Sanctuary, and later the Holy Temple in Jerusalem. Though the Temple was destroyed, the custom of donating the half shekel (which still has the force of a Biblical commandment for observant Jews) has persisted, and it is customarily given before Purim.

The basic issue for the “value” of the half shekel, as well as the other monetary values described in the Torah, said Rabbi Ishon, is that Biblical values were related to the weight of silver pieces that were used as money at the time (coined currency not having come into widespread use until hundreds of years after Mosaic law was instituted).

Of course, as with so many other matters of Jewish law, there are numerous opinions among halachic authorities on the proper formula for determining these values (how much silver to include, among other issues). The Institute offers different values in modern money corresponding to these opinions, although it publishes an “official” value based on a compromise of the opinions.

“The ‘exchange rate’ changes daily,” said Ishon. “We look at the representative rate of the shekel versus the dollar, and at the cost of an ounce of silver on world markets. We have software that averages out the amount on a daily basis, and that’s the amount we present, in modern Israeli shekels, that we present for each value.”

The “half shekel index” is just one vehicle by which the Institute hopes to make Jewish law relevant to daily life in Israel, said Ishon. “We established the Institute based on the belief that the Torah is alive, and that it can, and must be implemented in daily economic activities. The halachic sources include a great deal of discussion on financial matters that are relevant to daily life, with answers to the many moral dilemmas that face society and on the use of economic policy to deal with social issues.”