What’s on the back of a Mezzuzah: Likvod HaRav Ovadiah Hedayya ZTz”L
Tonight marks the Hillulah(Yahrtzeit for my Yiddish speaking readers) of Rav Ovadiah Hedaya ZTz”L the 12th Rosh HaYeshiva of Yeshivat HaMekubalim Beit El. He was the
Rav of many great Rabbanim, Rav Mordechai Sharabi, Rav Ovadiah Yosef, Rav Mordechai Eliyahu, Rav Yaakov Hillel(admittedly the latter learned also under Rav Sharabi) Rav Meir Yehuda Getz, Rav Ezra Shayyo, and many others far to numerous to mention. It seems typical these days that no matter what the individual derekh of the Rav was, after his passing we sit around and tell stories of the awesome miracles that he wrought, no matter how much they stretch belief, have been added to, or were simply made up(yes unfortunately this is at times the case).
However, as the derekh of the mekubalim of Beit El, and most especially their Roshei Yeshivot was always to walk in the way of tznua(modesty) and be satisfied with the title Rav HaHasid(to the effect that if one accepts the title of Zaken HaMekubalim he must step down from the position of Rosh Yeshiva, Beit El has to date lost four Roshei Yeshivot that way), it seems more fitting to honor the Rav by sharing a piece of his Torah, one considering my current state of busy-ness seems to me to be doubly fitting, namely dealing with what is written on the back of the Mezzuzah. I am bringing this from his sefer Yaskil Avdei volume 7, Yore Deah chapter 33, letter “bet” point “bet”… 
He has already said that anything other than the name שדי Shaddai on the back of the mezzuzah is forbidden this is his reasoning:
The reason for the issur(prohibition) even on the back, seems to be, that it reduces the holiness of the parchment, which was made with the intent of the holiness of a mezzuzah, if he will write upon it, some extra matter that is not directly related to a mezzuzah this desecrates its sanctity and lowers it from the point of holiness of a mezzuzah, only the name שדי “Shaddai”, which is a holy name and there is to it the holiness equal to a mezzuzah, may be added and nothing else, which would not have the holiness of a mezzuzah. Concerning the prohibition of writing angelic names or various pesukim from within, there isn’t to say that it is the same as writing them within a mezzuzah in which, where the point is that they lose their place in the world to come, rather on the outside it is simply a prohibition, that is speaking of the lowering of the sanctity, not that they would lose their place in the world to come Has V’Shalom.
Now to explain the matter a little bit more. There is a custom to write upon the back of a mezzuzah the angelic names כוז”ו במוכס”ז כוז”ו this custom comes from an early medievel custom to write kameot(amulets) on the backs of mezzuzot. The Rambam and other poskim forbade this, but some retained the custom of writing these three angelic names. Sephardim as well have forbade this, though at some point someone wrote to Rav Hedayya to ask him concerning it. His answer is above. To elaborate just a bit if I might a sefer Torah has a holiness corresponding to the world of Atzilut(the highest and holiest of the four worlds). A mezzuzah, because it is a Mitzvah D’Orraitta(a Torah Commandment) has a holiness corresponding to Beriah of Atzilut(each world is broken into four worlds, thus of the four levels of holiness within Atzilut, this is the second highest).
Angelic names, especially those we have access to post destruction of Beit HaMikdash, are from the world of Yetzirah(most specifically Asiah of Yetzirah, meaning the least holy realm of that spiritual world). So thus, Kabbalistically speaking, when one writes the names of these angels on the back of a Mezzuzah he causes the Mezzuzah to drop from nearly the most lofty level of holiness possible, to a very low level. Since, also Kabbalistically speaking, the point of a mezzuzah(aside from fulfilling the will of our Creator) is to bring holiness into the home, and to safeguard that holiness, it is fairly counter-productive to to so lower the inherent holiness of a mezzuzah. 
One last word. Whether this is taken, as the Ramchal held, to simply be metaphorical, or as the Leshem, quite litterally, either way maintaining the ancient superstitious practice(bet you never thought you’d here a Kabbalist say that) of putting these angelic names on the back of a mezzuzah should be given serious consideration. If you are Sephardi, the weight of halakha is quite against it(all of the Gedolim have ruled that they are only kosher b’diavad, so if you have paid good money for a mehudar mezzuzah and have these names there… sorry). Whereas for Ashkenazim it is a bit trickier and one should consult their local competent Orthodox Rabbi/posek.
A word about the photos. The first is of course the Rav. The second is Rav Hedayya giving a shiur in Eitz Haim the Rabbanim sitting, going from the right, Rav Mordechai Attiyah, Rav Yissachar Abuaziz, Rav Avraham Haim Shachror, Rav Yitzhak Kaduri, Rav Mordechai Sharabi, Rav Yosef Ovadiah Shayyo, Rav Shaul David Hai Meolam, Rav Ezra Ades, Rav Reuven Zamir, Rav… Rav Barukh Hedaya.
The last photo is of two Mezzuzot. One written by me, which is alef alef mehudar(according to Mishmeret Sofrim, under Rav Alfasi) the other is a Mezzuzah that purchased some years ago for $100(just the klaf) that was supposed to be ultra-ultra-Mehudar and is certified as such by the Va’ad Mishmeret Stam, but that Rav Ovadiah Yosef and Rav Alfasi have both said is only Kosher b’diavad, along with a warning to only seek psak Halakha on sephardi issues from Sephardim… lesson learned).
Which brings me to my second point, for those of you who have wondered whether(or why) I am not certified by Mishmeret Stam and only seek certification from Yad Rafael(Bnei Brak) and Mishmeret Sofrim(Yerushalayim) both of whom are Sephardi, that is your answer. The halakhot are sufficiently different, that it really does make a difference.
Interesting piece of trivia. We still use those same benches and tables. You kinda get to pick which Gadol’s spot you sit in.
For Ashkenazim, is there an opinion that one should try to have a mezuzah with these angelic names? Could one choose, for their personal practice, to just use mezuzot without the angelic names?
The Rama Y”D 288:15 עוד נוהגין לכתוב מבחוץ כוז”ו במוכס”ז כוז”ו נגד ה’ אלקינו ה’ ויהפוך אלא האותיות מכתיבת המזוזה כדי שיגיע כל אות נגד האות שמתחלף בו באלפ”א בית”א Also we are accustomed to write on the outside[angelic names] opposite Hashem Elokeinu Hashem and to write them upside down from the writing of the mezzuzah in order that each letter will be in the place corresponding to the letter that comes before it in the Aleph Beit.
These angelic names are derived from taking the letter in the aleph beit immediately after the letter of the corresponding name of G0d. For example, י becomes כ and ה becomes ו. Now according to the Rama here This is the custom of the Ashkenazim to write them. Whether an Ashkenaz can opt out of this custom or not, is really for one to ask their own competent Rav.
So, if an Ashkenazi would follow the custom of putting the angelic names on their mezuzot, does Harav Ovadiah Hedayya’s rationale still have bearing on them? Are they reducing the holiness of their mezuzot even though they have to because of their rav’s ruling? Or do spiritual realities differ for Ashkenazim and Sepharidim according to the halaha of each?
I asked this question of several Ashkenazim this evening. My understanding is that Ashkenazim who adhere to the teachings of the Arizal(i.e. mekubalim) do not have these angelic names written on the backs of their Mezzuzot. However, beyond that, one would have to ask their own Rav.
love the pictures… just wow. in their element!
I tried to make them high enough quality that if someone wanted to do an image grab that they could.
The one of the shiur was taken in 1951, that was when Beit El had just moved out from sharing space in Nahar Shalom and taken up residence in their, now permanent(unfortunately) building on Rashi street.