When a businessman establishes and runs a business, he shouldn’t rely on his own understanding and analysis, because his bias may lead him to err. Instead, he should base his conduct on the Torah’s directives, and if he is in doubt, he should consult a Rov. Whatever the endeavor, he should find out what Torah says about it and follow its guidance completely.
For example, he should make sure his economic growth does not encroach on another’s livelihood and is not associated with illicit behavior, chas veshalom. On the contrary, he should act beyond the letter of the law, in a way that is viewed as proper not only by himself but also by others.
The Torah says, “Rejoice, Zevulun, in your pursuits, and Yissachar, in your tents of study.” When a person who belongs to the category of Zevulun—namely, a businessman—ensures his conduct is based on the directives of Yissachar—Torah, Hashem promises that he will rejoice in his endeavors. He will experience great success and earn a maximum of profit, while keeping stress and frustration to the bare minimum.
Sichah of 7 Tishrei, 5751 (Sefer Hasichos 5751 vol. 1, pp. 28–29)


The Alter Rebbe explains that the mabul was not simply a punishment. Just like the water of a mikvah, which contains forty se’ah, the forty-day mabul purified the world from the impurities that had previously filled it.
The worries that can overwhelm a person trying to make a living are referred to as “torrents of water.” Just as the waters of the mabul purified the world, these worries cleanse him from unwanted elements.
A mikvah represents bittul—indeed, טבילה shares the same letters as
הביטל . By being batel and leaving your yeshus and self-centeredness
behind, you become elevated and can absorb holiness.
This is the real reason why a person may be inundated with business-related worries. Although they temporarily disturb and confuse him, they accomplish that his yeshus becomes broken, allowing him to be a vessel for holiness.
And since these worries are there not to punish but to cleanse, as soon as he allows them to accomplish their goal—be it in one instant—there is no need for them to remain, and he can enjoy a pleasant existence, both materially and spiritually.
Likkutei Sichos vol. 1, pp. 4–5