The general gravity with which business ethics are treated in Jewish thought is illustrated by the widely quoted Talmudic tradition (Shabbat 31a) that in one’s judgement in the next world the first question asked is: “were you honest in business?”
The Admor of Belz, Rabbi Aharon Rokeach, in discussing the angels descending and ascending on the ladder seen in the dream of Ya’akov, notes that the gematria value of sulam, ladder, is equivalent to that of kesef, money. The teaching here is that while a few are able to ascend spiritually in the way they earn and spend their money others, instead, descend here. Indeed, therefore, “nowhere in the whole field of human activity are the lusts and needs that need separation and religious guidance greater than in this field of human activity.”
Prohibition of monetary deception (ona’at mamon)
Leviticus 25:14 teaches: “When you sell anything to your neighbor or buy anything from your neighbor, you shall not deceive one another.” The Talmud (Bava Metzia 49b and 50b) and later codes (Rambam, Mekhira, Chapter 12) expand on this verse to create a series of specific laws prohibiting ona’ah, monetary deception. The prohibition is on the sale of an article at so much more, or to the purchase of an article at so much less, than its market value that fraud or the taking of an undue advantage is presumed.
Prohibition of verbal deception (ona’at devarim)
Leviticus 25:17 teaches: “Do not deceive one another, but fear your G-d, for I the Lord am your God.” Since Leviticus 25:14 was understood as referring to monetary deception, the Talmud concludes that Leviticus 25:17 refers to verbal deception, “ona’at devarim.”
In Baba Metziah (iv. 10), the Mishnah proceeds: “As there is ‘wronging’ in buying and selling, so there is ‘wronging’ in words; a man may not ask, ‘What is this article worth?’ when he has no intention of buying; to one who is a repentant sinner it may not be said, ‘Remember thy former conduct’; to him who is the son of proselytes one may not exclaim, ‘Remember the conduct of thy forefathers’; for it is said, ‘Thou shalt neither vex a stranger, nor oppress him'” (Ex. xxii. 21).
The Torah does legislate charging a fair price: “And when you sell something to your fellow, or buy from the hand of your fellow, don’t oppress each other” (Leviticus 25:14).This verse forbids selling an object far above the usual price, or buying one far below this price.
However, the essence of this law is not the problem of the fair price per se. “Just price” doctrine, which was a major topic of ancient jurisprudence, is given scant attention in Jewish law. Rather, the problem is one of misleading the customer. The baseline price is not determined by any intrinsic evaluation, but rather by the normal selling price. The idea is that a customer has a right to expect that a particular merchant is selling for a price similar to that of other comparable establishments. He had no intention of making a transaction at an unfair price, so the sale is void.
There is a hint of this theme in the word “to oppress”; the problem is a human one of deceit and exploitation, rather than a specifically economic one of obtaining an unfair price.
While Jewish tradition doesn’t interfere with wage negotiations between employer and employee, it does recognize that it’s just not reasonable to pay a qualified worker a sub-standard salary and expect him to work at the level of his fairly-compensated peers.