The previous Mishna (Mishna Pesachim 3:1, see Pesachim 42a) listed a number of different chametz-based products including ‘kutach’ – which is a Babylonian dip made from sour milk, bread crumbs and salt, and in today’s daf (Pesachim 43a) we are taught that the reason why the Sages specifically listed these products was כדי שיהא רגיל בהן ובשמותיהן – “so that we should be familiar with these products and their names”.
In fact, as a way of showing why it is so important for people to know the meaning and ingredients of specific products, the Gemara then relates how a certain resident of Israel came to Babylon and asked his hosts for a condiment to accompany the meat which he had with him. Upon hearing the them say among each other, “serve him kutach”, he abstained from what they had prepared. Of course, had he not known what ‘kutach’ was, he would have erroneously eaten meat and milk together, and had it been Pesach, he would have also erroneously consumed chametz.
As a parent of children with severe allergies, I know only too well the importance of being aware of the ingredients of certain products, and in a world where there are many people who suffer from, in some cases, life-threatening allergies, I believe that all of us “should be familiar with products and their names”, so we can avoid even greater dangers to life than erroneously eating food in which meat and milk has accidentally been mixed.
But in addition to this, I believe there is a further point that we can draw from the idea that כדי שיהא רגיל בהן ובשמותיהן – “we should be familiar with these products and their names”, which is that those who are called upon to determine matters of Jewish law must ensure that they are familiar with the products and names of items that are used by their followers and questioners.
For example, as demonstrable from responsa penned by Rabbi Yitzchak Rubin (as printed in Havieini Chadarav p. 277) and Rabbi Yitzchak Yosef, it is essential for halachic decisor addressing questions of Hilchot Shabbat in the COVID era to know what an infrared thermometer is and how it operates. Similarly, as demonstrable from the responsa penned by Rabbi Nachum Rabinovitch (Siach Nachum No. 61), and provided by Nishmat’s Yoatzot Halacha (Nishmat HaBayit No. 49), it is essential for a contemporary halachic decisor to know what a Nuvaring is and how it operates. And undoubtedly, a halachic decisor who renders decisions about the financial world must know and understand what Bitcoin is.
Ultimately, just as the Mishna teaches us about Babylonian kutach, Median beer and Idumean vinegar to ensure we are familiar with these products and their ingredients, so too, each of us should be familiar with the ingredients of popular foods, while halachic decisors should ensure that they are up-to-date with the products that are currently being used in society and by those who turn to them for guidance and answers.