Understanding the Din of a Bosis (base for a forbidden item) in the laws of Muktza



I want to place bars of sweet-smelling soap as a drawer freshener inside dresser drawers. Would I then have a problem opening those drawers on Shabbos? It’s just a plain, fragrant bar of soap sitting in the drawer. It doesn’t spray anything. I would open the drawer to take out items I need on Shabbos.

I understood from halacha I’ve learned that if there are Muktza items in a drawer together with items I need on Shabbos, I would need to have something like a bencher in the drawer in order to open it. For instance, I have a medicine drawer that contains medicine I need on Shabbos together with creams I don’t use on Shabbos. I put a bencher in that drawer. Is that necessary, or is it going too far?



I’ll try to give a brief overview:

When a muktza item is placed (purposely, before Shabbos) alone on top of a non-muktza item, it may render the non-muktza item as muktza as well. This is called “bosis l’dovor ho’assur” – a base for a forbidden item.

However, if the muktza item is laying along with a non-muktza item on top of something, and the non-muktza item is of higher value/importance than the muktza item, it does not render that thing as muktza. This is called “bosis l’issur ul’heter” – a base for a forbidden and permitted item.

Based on this:

If your drawer has medicine (or anything else) that is of higher value/importance than the cream, it is no problem to open on Shabbos. Same applies with the soap.

It should be noted that one may not create a good smell on Shabbos if the purpose is the good smell (as opposed to just getting rid of a bad smell). Thus the fragrant soap should not be placed there on Shabbos.



בקצוה״ש קמז בבדה״ש יב, ושם קכו, לב בסופו שסבון הוא כשמל״א. אבל יש הסוברים שדינו כמוקצה מחמת גופו לפי שאינו בתורת כלי והשתמשות בו הוא בדרך כילוי ודלא כנר שעומד ליהנות מאורו. וראה שו״ת אג״מ, ה,כב, טו. שלחן שלמה שח, לא, ג. שלמי יהודה ט הע׳ ח. חוט שני ח״ג נג, א. וכמו דיו – ראה מנחת שבת פח, כה, ח. ואף שיש מתירים להשתמש בו בשבת – ראה שו״ע אדה”ז בסימן שכו סעיף י מהמג״א – אולי קאי רק בדעת האוסרים.