Skip to main content

Thought for the Day: Reason Not to Use Glazed Pottery on Pesach -- Not Just a Theoretical Concern

I am so excited.  I get to pull an example from physics to explain why learning the tiny details of halacha are so important.  Life is good.

Let's talk about quantum mechanics.  You've probably heard of the uncertainly principle.  For an electron, than means that you can't know it's position better than the size of an atom.  Do get a feel for how big that is, if the nucleus of an atom was blown up to the size of a ping pong ball and put at the top of the Willis Tower, then you would only know that its electrons are somewhere in downtown Chicago.  That's a big deal for the atom.  On the other hand, if you took a real ping pong ball, the uncertainty in it's position is less than the size of the nucleus of an atom; not a big deal, not even measurable.  So who cares if quantum mechanics is the more correct description of nature?  Well... without quantum mechanics, we would predict that that the entire universe would wink out of existence in less than a microsecond in a flash of ultraviolet light.  Quite psychedelic; absolutely worng.

Knowing the tiny details of why halacha goes the way it does can have similarly dramatic effects.  For example, we don't kasher pottery for Peisach use.  Pottery absorbs and you can never get all of the absorbed matter out, so we we have to get new.  What about glazed pottery?  That is, pottery with a thin coating of glass over it?  Normally we say that glass doesn't absorb, but for glazed pottery we are stringent and treat the glass as pottery.  Ipso facto, we don't use our non-Peisach glazed pottery on Peisach.

But why do we treat glazed pottery like pottery?  There are two explanations proposed:

  1. Once the glass is bonded to the earthenware, it takes on the characteristics of earthenware.
  2. Glass as thin as you find on the glaze is actually porous, just as earthenware is.
Now, then; who cares?  Well, if the reason is like (1), then bonding the glass to something that is kasherable would mean that glazed thingy is also kasherable. One the other hand, if the reason (2), then you are stuck.  Who cares?  As it turns out, you really, really care about this.  Porcelain enamel is glass glazed onto steel.  The inside of your oven is lined with that.  Do you like being able to kasher your oven for Peisach?  (If you think that's no big deal, check with your wife.  Let me know how that goes for you when you recover.)  However, even more than that (WHAT? More than the wrath/concern of a Jewish woman before Peisach?!  Yep...): The food industry used porcelain enamel coated reactor vessels all (steel for strength, glass for corrosion resistance and taste neutrality).  The underlying reason, therefore, affects nearly all the processed food you enjoy.  (Ok, so maybe not more than the wrath/concern of a Jewish woman before Peisach, but certainly in the same league.)

As long as were talking about this, there is one more reason the Mishna Brura mentions for this stringency: Bran (husks of wheat kernels) is used in the glazing process.  Even though bran doesn't ferment, that's a problem because either:

    1. Bran is a part of the wheat kernel; so even though it doesn't ferment, the Torah still calls it chameitz
    2. It is a stringency for Pesach because... well... it's Pesach, for crying out loud
As it turns out, there is a process for making alcohol that starts with bran, and alcohol is used all over (not just for drinking), so...
Labels:

Comments

Post a Comment

Popular posts from this blog

Thought for the Day: Love in the Time of Corona Virus/Anxiously Awaiting the Mashiach

Two scenarios: Scenario I: A young boy awakened in the middle of the night, placed in the back of vehicle, told not to make any noise, and the vehicle speeds off down the highway. Scenario II: Young boy playing in park goes to see firetruck, turns around to see scary man in angry pursuit, poised to attack. I experienced and lived through both of those scenarios. Terrifying, no? Actually, no; and my picture was never on a milk carton. Here's the context: Scenario I: We addressed both set of our grandparents as "grandma" and "grandpa". How did we distinguish? One set lived less than a half hour's drive; those were there "close grandma and grandpa". The other set lived five hour drive away; they were the "way far away grandma and grandpa". To make the trip the most pleasant for all of us, Dad would wake up my brother and I at 4:00AM, we'd groggily -- but with excitement! -- wander out and down to the garage where we'd crawl
Post a Comment
Read more

Thought for the Day: אוושא מילתא Debases Yours Shabbos

My granddaughter came home with a list the girls and phone numbers in her first grade class.  It was cute because they had made it an arts and crafts project by pasting the list to piece of construction paper cut out to look like an old desk phone and a receiver attached by a pipe cleaner.  I realized, though, that the cuteness was entirely lost on her.  She, of course, has never seen a desk phone with a receiver.  When they pretend to talk on the phone, it is on any relatively flat, rectangular object they find.  (In fact, her 18 month old brother turns every  relatively flat, rectangular object into a phone and walks around babbling into it.  Not much different than the rest of us, except his train of thought is not interrupted by someone else babbling into his ear.) I was reminded of that when my chavrusa (who has children my grandchildrens age) and I were learning about אוושא מילתא.  It came up because of a quote from the Shulchan Aruch HaRav that referred to the noise of תקתוק
Post a Comment
Read more

Thought for the Day: David HaMelech's Five Stages of Finding HaShem In the World

Many of us "sing" (once you have heard what I call carrying a tune, you'll question how I can, in good conscience, use that verb, even with the quotation marks) Eishes Chayil before the Friday night Shabbos meal.  We feel like we are singing the praises of our wives.  In fact, I have also been to chasunas where the chasson proudly (sometimes even tearfully) sings Eishes Chayil to his new eishes chayil.  Beautiful.  Also wrong.  (The sentiments, of course, are not wrong; just a misunderstanding of the intent of the author of these exalted words.) Chazal (TB Brachos, 10a) tell us that when Sholmo HaMelech wrote the words "She opens her mouth Mwith wisdom; the torah of kindness is on her tongue", that he was referring to his father, Dovid HaMelech, who (I am continuing to quote Chazal here) lived in five worlds and sang a song of praise [to each].  It seems to me that "world" here means a perception of reality.  Four times Dovid had to readjust his perc
Post a Comment
Read more