In the highly practical chapter of Hilchot Deot we have already had recourse to, the final halachah is all about acting with integrity. It begins:
A talmid chacham should conduct his business dealings in truth and faith. His “no” means “no” and his “yes” means “yes.”
The first notable thing about Rambam’s discussion is that it is addressed to a Torah scholar, who must set the example to every Jew of how one conducts himself in business. And the first requirement is that what emerges from one’s lips is sacred. We must keep our promises even if it is to our disadvantage. In business, market conditions are constantly shifting. Continuing with the sale or service – even if, say, the cost of offering it unexpectedly rose – affirms both truth and good faith: The former establishes the Jewish businessman’s reliability and the latter his trust in Hashem, the source of our wealth. The Jewish businessman knows that God will compensate our losses.
He is stringent with himself in his accounting, but gives and concedes to others when he buys from them, and he shouldn’t be exacting with them. And he pays for merchandise immediately.
This honesty we described above, in which the Jewish businessman would rather bear a loss than not fulfill his word, he applies to himself, but to his counterparties he gives the benefit of the doubt and offers easy terms for their unpaid balances. And by paying his debts immediately, he preempts even the momentary impression that he isn’t going to pay. Not only does such conduct sanctify God’s Name, but it furthers people’s desire to do business with him, as it enhances the attractiveness of doing business with a talmid chacham, as we’re all meant to be.
And he does not act as a conditional guarantor or unconditional guarantor or become a debt collector for another lender.
Although the talmid chacham can be relied upon to pay anything he owes post haste, he doesn’t accept responsibility for debts he may be unable to pay. Thus, if he were to guarantee his friend’s debt, conditionally or unconditionally, and then the friend, through no fault of his own, became unable to pay off his debt, our Torah scholar risks his reputation if he cannot step in immediately and pay his friend’s debt as he would his own. The idea is that one does not act out of the goodness of his heart if he risks a failure to sanctify God’s Name through immediate action to make good a loss – or by putting himself in a position where he must pressure the borrower to pay up or the lender to extend the loan. The same principle applies to a debt collector, whose duty to the lender restrains him from acting with the magnanimity towards the debtor that should characterize a talmid chacham.
He obligates himself in matters of buying and selling where the Torah does not obligate him so that he can stand unalterably by his word. Yet if others are liable to him by law, he extends and forgives, lends and is generous.
Beyond keeping one’s commitments even when market conditions make doing so unfavorable, the nuance added here is that the talmid chacham’s verbal commitments are paramount even when he never performed an act of acquisition, and thus is not legally bound to move forward. But when the shoe is on the other foot, the talmid chacham does not insist on his rights. And while, as we learned above, he does not involve himself in other people’s loans as a guarantor or collector, he himself provides loans and, when necessary, forgives them. The halachah concludes:
He should not encroach upon his friend’s craft nor should he trouble anyone in the world all his life. The general principle is he should be one of the persecuted and not the persecutors, one of the insulted and not the insulters. And of a person who performs all of these deeds and their like, Scripture says: “And He said to me: You are My servant, Israel in whom I am glorified.”
The Rambam concludes this halachah on integrity in business by reaffirming the overarching idea that a talmid chacham conducts his business dealings with honesty and good faith. He has no reason to enter the booming business conducted by a colleague because he trusts that God will grant him and his colleague what He desires to bestow. He therefore acts with piety, in the spirit of “what is mine is yours and what is yours is yours.” This makes good business sense too, as what is hot today is cold tomorrow. Trends in business are constantly shifting, and by the time the temptation to jump into a profitable area persuades you, it has already persuaded several others, and then suddenly you find yourself in a saturated market. The talmid chacham’s approach is thus less about zigzagging and more about constancy. Markets may wax and wane, but his reputation for integrity only grows.
Before we are examined, it is immensely helpful to know the questions we will be tested on. Those six questions which we are asked on the Day of Judgment underscore the importance of Torah, which make up half of them. Earning a living and raising a family emerge from two others. If we do all of these things, we certainly will anticipate salvation, the sixth item on the divine checklist.
In reality, all of these issues are interdependent. We can’t do anything properly without the constant guidance of Torah and immersion in its holiness. But as our challenge is not merely immersion but also imparting something of value, what we do to uplift the material world will decisively show if we passed our test in life.
 Deot 5:13
 As Mishlei 6:3 advises a guarantor to do, but which is uncharacteristic of the talmid chacham that the Rambam describes.
 Compare Rashi, Shevuot 31a s.v. זה הבא בהרשאה.
 Yeshayahu 49:3.
 Avot 5:10.