A beraita quoted in b. Pesahim (6a) states that one must commence study of the laws of Pesah 30 days before the holiday; the practice as codified in the Shulhan Arukh (OH 429:1), and the Mishnah B’rurah (SK 2) is that study should begin on Purim itself. In order to safeguard JTS’s reputation as a center of halakhic stringency, I thought I would address a topic that is often neglected to the detriment and indeed peril of the kosher consumer: namely, the protocol for kashering one’s hands before Passover.

As you know, ceramic utensils are considered porous and therefore are impossible to kasher for Pesah. What, however, about the skin of our hands? You will recall from high school biology that the skin is a semi-porous membrane that absorbs and emits various substances. Try chopping an onion or crushing some garlic—your hands will reek for hours or even days. If you chop jalapeno peppers, remember not to rub your eyes! Indeed, the laws of kashrut recognize the special status of spicy foods as דבר חריף, capable of transferring flavor to a second utensil even without the application of physical heat. A knife or board that has had onion or garlic chopped on it will be considered to take on the kashrut status of any other food substances exposed to that surface at that time.

Obviously there is no avoiding a d’var harif on Pesah, since we have a mitzvah d’oraita to eat maror. Handling any spicy foods and then hametz renders the hands hametzdik. Touching Passover foods with hametzdik hands contaminates them and makes them forbidden to eat or even own on Pesah. It’s a bit like the myth of King Midas—whatever you touch becomes inedible. You can sell your hands for Pesah, of course, but this is complicated since you must then “make kinyan” by lifting the pen with your teeth. So, if selling your hands is not workable, how about kashering them? Not so simple.

A recent study documented the persistence of onion enzymes on the skin for as long as 36 hours after exposure. This means that the hands have the status of notein ta’am—the transmitter of a flavor. In general regarding basar v’chalav, meat and milk, we can be lenient and assume that the received flavors will be bateil bishishim, annulled through a ratio of 60:1, but regarding Passover, hametz is forbidden at the atomic level of bikhol she-hu. Thus, we have a problem. If you were to handle onions and then, for example, touch a bagel on Erev Pesach (before 10 AM of course), then some of the hametz would become embedded in your skin. Since the onion essence would persist for no less than 36 hours (it could be longer!) any other food substance such as matzah subsequently touched by your hands would by virtue of the persistent sharp onion flavor receive the transfer of chametz and be forbidden to a Jew for ownership, profit or ingestion. If you were to touch something spicy like horseradish on Pesach even after the 36 hours, it could re-awaken the forbidden chametz flavors in your skin and render anything you subsequently touch chametz. This is called hozeir v’ne’or (zombie hametz that comes back to life–See SA OH 447:4).

As the Sages like to say אף על פי שאין ראיה לדבר זכר לדבר , (m. Shabbat 8:7) even though this matter isn’t stated explicitly it is at least hinted at. Where? Consider Hillel’s famous sandwich—why maintain the antiquated custom of placing the maror between two sheets of matzah when there was no longer any paschal lamb to fulfill the verse עַל מַצּוֹת וּמְרֹרִים יֹאכְלֻהוּ:? It would seem that the real concern was to use a non-reactive substance—matzah—to shield the hands from the sharp or bitter herb—maror—lest it reactivate the hametz embedded in the hands. This ingenious solution is to be commended, but we can hardly eat everything on Pesah sandwiched between matzot, and this is an intolerably risky strategy.

What is to be done? Several solutions have been offered:

According to the 19th century super-commentary to Yoreh Deah known as “Okeir Taam v’Reah” the best solution is hagalah. Simply heat a vat of water to the boiling point and then immerse your hands for 20-30 seconds until the skin is thoroughly blistered, then transfer to ice-water. This should remove the onion oils in your skin, though it may make it difficult to use your hands to hold the kiddush cup, raise the matzot etc. The Camelback Kiddush Cup™ is one solution—you wear it mounted on your back, and sip the four cups through the line, pausing between “cups.” The deluxe edition has a separate bladder for each cup of wine that fulfills the GRA’s definition of a revi’it (there is also a mehadrin mishugain version that follows Rav Shikker of Dublin that a revi’it is a “wee pint”). Even so, you may need to use your hands during Pesah, e.g. to lift the matzah. For these cases you can turn to a minor who has not handled onions to spoon-feed you. One added benefit of hagalat yadaim is that you get to experience the plague of “boils” in a more realistic fashion than most seder participants could ever imagine.

Another solution, offered by Torat Ha-Afar, is ne’itzah. Usually this method is used to kasher knives by thrusting them into packed earth ten or more times. Many people also leave the flatware buried for extended periods of time just to be sure. In our case, this type of kosher exfoliation can be accomplished by thrusting your hands into packed dirt—preferably loaded with pebbles—9 times and then leaving your hands buried for at least 12 hours. Some people set a flower pot by their bed so that they can sleep on their side with the hands resting underground in fulfillment of Daniel 12:2, ורבים מישני אדמת עפר יקיצו, “Many who sleep with dusty earth will awaken.”  This solution is less painful than hagalah but may be uncomfortable for those accustomed to midnight snacks and trips to the restroom.

An increasingly popular solution is to enter a sweat lodge prior to the holiday. This method, mentioned in Sodot Ha-Ma’arav, can be thought of as similar to hagalah, except that the heat comes from within and your pores are cleaned by the excretion of vital fluids. This is in fulfillment of בזעת אפיך תאכל לחם, “by the sweat of your brow shall you eat bread” (Gen. 3:19). Some have reported hallucinations of hametz during the final hours of sweating. Emerging from the dark, dank bath of steam into the cool air is said to allow one to experience, “hayav adam lirot et atzmo k’ilu hu yatza mi-Mitzraim lailah” that s/h has actually made the night exodus. However, since sweat lodges often leave one dehydrated and incapable of drinking alcohol, this solution may be incompatible with the rigors of the seder. Consult your physician and shaman for individual advice.

Finally, the safest solution is simply to wear surgical gloves for the duration of Pesah. This way your hands are protected from having dormant hametz particles re-awakened through exposure to a d’var harif such as horseradish or endive during the festival. This solution has unfortunately been limited to Sephardim since latex gloves are often dusted with cornstarch, and Ashkenazi poskim today are concerned about avak kitniyot or trace amounts of forbidden legumes. Given the CJLS’s recent decision to permit kitniyot even to Ashkenazim in order to avoid minhag shtut (a foolish custom), we may now permit the wearing of surgical gloves for the duration of Passover. You’re welcome! Hag kasher v’sameah.

I hope that this Purim preview of Hilkhot Pesah helps you enjoy the former festival. In the highly unlikely event that you have read this all the way through and accepted it as serious “halakhah lima’aseh,” please don’t! Rather, you may treat this letter as יד סולדת בו, too hot to handle…