Rav Yosef Dovid Josilowsky Question: We have stated that a Modaah works to negate a…
Case: Reuven is walking down the street with $20 in his pocket, not meant for any specific purpose. Shimon comes over and asks to borrow $20.
Question: Does he have a chiyuv to lend Shimon the money?
Answer: In general, the answer is yes. Chazal teach us that it is a Torah obligation to lend money that is not currently in use to someone who asks for it [provided it can be properly secured e.g. by taking a collateral]. We will find that the mitzvah of lending cash is in many cases mandatory even if there are opportunity costs, such as if you would need to forgo interest.
This requirement is not as clear cut when it applies to things other than money, such as items that one may want to borrow. For example, if you have a lawn mower and your neighbor would like to borrow it, you are not obligated to allow him to use it in the way you would be had he asked to borrow money. The Chofetz Chaim and other Poskim indicate that items do not fall under the category of kessef (cash), and therefore, you have the flexibility to decide whether or not to lend it out. However, there is a general mitzvah to do chessed, and lending out items which aren’t cash would fall under this category.