If someone carelessly scraped his shoe on my Shabbos trousers, may I dust it off? 

The gemora Shabbos 147a says that one who shakes his garment on Shabbos violates a Torah transgression, and is required to bring a sacrifice. Rashi [1] explains the gemora to be referring to shaking dust off one’s clothes. The Rama quotes this opinion and is the accepted halacha. [2] Therefore one may not dust jackets, hats, and trousers, or any clothing. It is irrelevant whether one dusts one's clothing with a brush, a rag or with one’s hand, the point is that one is cleaning clothes. There are other criteria involved, see further. The Mishna Berura suggests that one be careful, on Shabbos, not to place one’s hat on a dusty surface, because it might easily lead to the desecration of the Shabbos. 

Is there a difference whether they are Shabbos trousers or regular trousers? 

The gemora continues that this prohibition only applies to new and dark clothing, and to clothing one is meticulous about being dirty. New is defined as a garment that still looks fresh and new, see footnote. [3] Dark is a criteria; because dust on a light colored-garment goes unnoticed and dusting it is not considered cleaning.  

What if I would wear those clothes without dusting? 

Clothing that one normally wears without bothering to dust before wearing may be dusted on Shabbos, because it is not considered “dirty”, and hence the dusting is not called cleaning.

Clothing that one would not wear without carefully dusting beforehand, may not be dusted and cleaned on Shabbos, even without the aid of water.

Therefore, Shabbos trousers, suits and hats – dark clothing that usually look new, may not be dusted on Shabbos, because one is makpid – meticulous about their appearance, and dusting them involves a Torah prohibition.

Even though the Mechaber did not prohibit dusting clothes, Sephardim should also refrain from dusting clothes on Shabbos. [4] 

What is the halacha with regards to shaking off dandruff and feathers? 

We must differentiate between dirt that has penetrated a garment, where the laws of libun (cleansing of garments) are applicable, and dirt that sits atop the garment. “Cleaning” a garment applies to cloth which has become dirty: consequently feathers and straw may even be stuck between the threads, but they do not “dirty” or soil the garment, and therefore removing feathers and straw from a garment is not “cleaning” it. One may even remove dust sitting on top of a jacket, because in such a case the jacket is not “dirty”. A dusty sleeve or trouser leg may be lightly dusted to remove the outer layer of dust that has not penetrated the garment, but extreme care must be taken not to overdo it, because there is only a fine line between dust that has penetrated the garment and the dust that has not.

Dandruff also rides ones shoulders and may be gently patted off one’s clothes. 

Is one permitted to shake out a wet raincoat or a wet sweater? 

Other Rishonim [5] explain the above-mentioned gemora (Shabbos 147a) as referring to clothing wet from dew. The Shulchan Aruch explains that shaking such a garment is as effective as laundering, and therefore one would be violating the transgression of libun. All the same criteria apply as were mentioned with dusting, i.e. new, dark and meticulous. Therefore, when one takes in a jacket, which was left in the open overnight and is drenched with dew or if after one comes in from the rain and removes a rain-drenched suit, one must take care not to shake out the dew/rain, as it involves a Torah prohibition. 

Is one really not allowed to fold one’s tallis on Shabbos? 

Rashi tells us in the Mishna in Shabbos 113a, that the reason one is forbidden to fold clothes is because it is as if one is repairing them. Either folding into their creases ‘repairs’ them [6] by accenting the folds, or folding irons out [7] the creases.

Based on the gemora, the Mechaber [8] teaches us that when certain conditions are complied with, one may fold one’s clothes. The conditions are:

1.      One needs to wear these clothes again that Shabbos, and is folding them to keep them in good condition.

2.      One must fold them by himself, without the aid of a second person. The Mishna Berura [9] says that it needs to be folded in midair and not on a bench etc.

3.      The clothes have not yet been laundered. The M”B explains that before laundering they are still a bit stiff and do not crease easily, hence folding them does not appear to be much of an improvement.

4.      Only white clothes may be folded. It is more of an improvement to fold colored clothes.

5.      One does not have other clothes to wear besides these ones. 

Accordingly, one is forbidden to fold one’s tallis, as some of the conditions are not applicable. The first one being that the tallis is only worn for shacharis. Also, the tallis may have been dry-cleaned or washed.

However, the Mechaber quotes the Mordechai who holds that one may fold any garment not on its original folds. Hence one is allowed to fold a tallis in a different manner than one usually does.

 

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