It may surprise people to discover that the prohibition against lending at interest can affect their everyday lives. For instance, may one make a purchase on a friend's credit card and pay the credit card company directly? If one borrows a car with an almost empty gas tank, may one return it with a full tank? If one borrows a garment from a friend, may one have it dry-cleaned before returning it? If one borrows a child's suit for a wedding, may one add a small toy when returning the outfit? May a borrower buy an aliyah to the Torah for the lender? May one pay a caterer the full price in advance and ask for a discount in return? May an author who borrowed money to publish his work print an acknowledgement to the lender? May one borrow money in one currency and repay it in another? The answers to these questions are usually not an unqualified yes or no. Very often, the rulings vary with the particulars of the situation, and in some cases, there are differences of opinion among the poskim, Questions of Interest addresses all of these questions, as well as a host of others. Questions of Interest, which also includes extensive Hebrew-language footnotes which offer many illuminating sidelights and sources, will undoubtedly be of great interest to all readers, from the scholar who has an intimate knowledge of the subject to the layman who needs to be introduced to the basic concepts.
by Rabbi Yisroel P. Gornish