Taking excessive monetary loss into consideration TB Moed Katan 10

Although work is forbidden on the intermediate days of the holiday, we learned earlier that the Torah gave the sages the power to create exceptions. Up to now the exception under discussion was exertion. If the task required excessive exertion (טירחא יתרא), it was prohibited. If the task didn’t require a lot of hard work or at the completion of the task brought joy like preparing a banquet which requires a lot of hard preparatory work, but in the end eating the meal brings happiness, the task is permitted.

Daf TB Moed Katan 10 discusses the second exemption, the result will be a significant loss (בַדָּבָר הָאָבֵד). “§ And Rava also said: Any commerce is prohibited on the intermediate days of a Festival. Rabbi Yosei bar Avin said: But with regard to a matter that, if left unattended, will result in significant loss, it is permitted.” (Sefaria.org translation) Rashi and Tosefot define a significant loss differently.

 Rashi  ד"ה וּבַדָּבָר הָאָבֵד מוּתָּר defines it as a lost opportunity. An example of this definition in the Gemara is: “So too, it is taught in a baraita with regard to idol worship like this case: One may go . to a fair of pagan gentiles held on a day they have designated for idol worship and buy animals, slaves, maidservants, houses, fields, and vineyards from them. And he may write the necessary deeds and confirm them in their courts [arkaot] by verifying the signatures on the documents to prevent the sellers from appealing and retracting the sale. Although this behavior might be construed as a display of respect for the gentiles and their idols, it is nevertheless permitted because it is as if he were rescuing his property from their hands, as he would not have another opportunity to acquire these items. This indicates that time-sensitive transactions are considered like cases where one might suffer financial loss, and are permitted.” (daf Moed Katan 11b, Sefaria.org translation)

Tosefot ד"ה וּבַדָּבָר הָאָבֵד מוּתָּר defines it as a loss of money including the principle. An example of this definition is “Ravina had lent money to the residents of the fortress of Shanvata. He came before Rav Ashi and said to him: What is the halakha with regard to going to them now, on the intermediate days of the Festival, to collect my debt? Rav Ashi said to him: Since it is now that you will find them, whereas on other days you will not find them, as during the year these people would travel from place to place to earn their livelihood, this is treated like merchandise that will be lost, and it is therefore permitted.” (Sefaria.org translation)

Our sages were insightful enough to understand the importance of the mental state of their fellow Jews. How could somebody truly enjoy the holiday when they would be distressed every moment knowing that they would be losing a significant amount of money?! The sages were flexible in their approach to Jewish law to take in account the person’s mental state and permit commerce whether it represented a loss of principle or lost opportunity.