אַל תִּקַּח מֵאִתּוֹ נֶשֶׁךְ וְתַרְבִּית … אֶת כַּסְפְּךָ לֹא תִתֵּן לוֹ בְּנֶשֶׁךְ – You shall not take from him interest or increase…You shall not give him your money with interest.
The Torah absolutely forbids charging any type or amount of interest payments on loans. This prohibition is so severe that the Torah devotes five separate injunctions against it: once in Exodus 22:24, twice here, and twice again in Deuteronomy 23:21 and 22. The Torah even addresses a separate prohibition to the borrower against paying interest; he too is culpable for this sin.
To our minds, there seems to be nothing ethically or morally wrong with charging interest; it appears to be a natural way of doing business. Just as the owner of a house, a car, or any other object is entitled to remuneration for renting out the item, so too should a lender of money be entitled to a return on his capital. The borrower, for his part, may gladly agree to pay for the use of this capital.
Yet the Torah emphatically prohibits the taking of interest, even if the interest is lower than the going rate of banks or other lending agencies. At the same time, the Torah does permit taking interest from a gentile, although robbing or cheating a gentile is categorically forbidden—suggesting that the gentile has not been injured or exploited by being charged interest. Why the severity of the prohibition only in regard to our fellow Jews?
The prohibition of charging interest can be understood based on the Torah’s choice of the word אָחִיךָ, your brother, in describing the prohibition. True, there is nothing ethically wrong with charging interest. But if your own father or brother were to come to you for a loan, would you collect interest from them? Certainly not! This is the way the Torah wants us to consider the needs of every Jew. If your brother becomes destitute, when your fellow Jew becomes impoverished, he is to be viewed as achicha, your brother, your blood relative. Taking interest does not constitute a civil wrong, but rather a deficiency of high moral conduct.
Similarly, the laws of interest are found in the Yoreh Deah section of Shulchan Aruch, which normally deals with ritualistic precepts, rather than in the Choshen Mishpat section, which deals with civil law. Inserting the laws of interest in Yoreh Deah demonstrates that these laws are not categorized as mitzvos bein adam lechaveiro, to prevent exploitation of one’s fellow man. Rather, charging interest to a fellow Jew belongs in the category of mitzvos bein adam lamakom, between man and his Creator. (Halachic Positions, Vol. 5, pp. 82-84)