I am a 28-year-old “lefty” who performs all labor and activities with my left hand, with the exception of writing, which I do with my right hand. (This inconsistency was a result of my strong-willed grandmother’s insistence that her grandson was going to write the “normal” way!) The instructions given to me before my bar mitzvah were to put tefillin on my left arm, as a right-handed person would normally do. I recently began learning the laws of tefillin, and I see the matter is far from simple. Should I be wearing the tefillin shel yad on my right hand, as lefties do, since I am really a lefty except for writing? Does anyone wear the tefillin shel yad on both arms consecutively?


The good news is that the original psak you received at your bar mitzvah was not wrong. The better news is that the information you will now receive will assist you so that if you desire to ask the question again, you will understand the options. (One neednot ask any she’eilah twice, but in this particular case, there might be room to re-examine the issue, as we shall soon explain.)

The Gemara discusses two possible sources to explain why a left-handed person puts tefillin on his right arm. Rav Nassan learns from the juxtaposition of two pesukim — “U’keshartam l’os al yadecha” and“U’chesavtamal mezuzos beisecha” — that the tying of the tefillin (u’keshartam) is done by the same hand that does the writing (u’chesavtam). This means, then, that a person who writes with his left hand will put tefillin on his right hand, thereby tying it with his left hand. According to this derashah, left- or right-handedness is determined solely by which hand does the writing (even if a person was forced to use that hand in order to conform with societal “norms”).

The second source, Rav Ashi, determines from the word “yadcha” in the pasuk, “v’hayah l’os al yadcha uletotafos bein ainecha” that the tefillin is placed on the weaker hand — “yad kehah.” And Rashi adds that “yadchah” is lashon nekeivah, indicating the weaker hand. According to this derashah, the determining factor is which hand does most of the daily activities (e.g., using a fork or hammer or lifting heavy objects), and writing does not count more than any other activity. Once the stronger hand is identified, the shel yad is placed on the other hand.

Interestingly, an ambidextrous person dons his tefillin as a right-handed person would. This applies only to one who performs all activities equally with both hands. Many who profess to being ambidextrous cannot really write well with both hands and often do not perform other activities with nearly the same strength in both hands.

There is a dispute among the Rishonim and early Achronim about whether strength or writing is the deciding factor in determining which hand will be used.

The Shulchan Aruch quotes both opinions. The general rule of the Shulchan Aruch is that when two opinions are quoted and both are quoted as a “yesh omrim,” the halachah follows the second opinion. In this instance, the deciding factor is which hand does the writing. The Rema, who generally represents the minhag of Ashkenazim, agrees that the custom is to use the hand that writes as the determining factor. The Gra (Vilna Gaon), however, and others take the opinion that it depends solely on which hand performs most of the daily activities.

The Bach brings a third opinion that states that if either writing or the other activities are done by the right hand, then the man is considered a “righty” and wears the shel yad on the left hand. It is only when all activities and writing are done by the left hand that a person is considered a lefty. There are notable poskim who concur with this opinion.

HaRav Moshe Feinstein, z”tl, points out that it is difficult to declare that there is a clear minhag in regard to this matter. He points out a discrepancy between two sefarim, Rema and Darkei Moshe, both written by HaRav Moshe Isserlis, zt”l. The Rema states, “v’hachi nahug — that is the custom.” However, the Darkei Moshe states “v’nireh li linhog — it appears to me that that should be the custom.”

Rav Moshe then raises the possibility that one should be machmir and put the shel yad on each hand alternately, since it is prohibited wear tefillin on both hands at the same time, before putting on the shel rosh. Others suggest that the second shel yad should be donned at the end of davening. The advantage of doing this at the beginning of davening rather than at the end is that the berachah recited on the first shel yad will be chal on whichever hand is the correct one. If one puts on the second shel yad at the end of davening, no berachah can be recited.

In his written teshuvah, Rav Moshe rejects this approach because it is a difficult thing to do every single day. We also do not see that the earlier poskim suggested such an idea, even though it would cover both halachic opinions.

Interestingly enough, not only do other poskim endorse the suggestion that one should (although certainly not obligated to) try to wear the additional shel yad, but Rav Moshe himself has advised others to do so.

The story begins on the Lower East Side over forty years ago ….

Rabbi Mordechai Goldstein, Rav of the Mishkenos Yaakov community in Ramat Beit Shemesh, Eretz Yisrael, and the son of one of the leading poskim of American Jewry in the last generation, HaRav Tuvia Goldstein, zt”l, is left-handed. Nevertheless, when he was growing up, he was taught to write with his right hand. Although he wrote exclusively with his right hand, his left hand performed all other activities.

Before his bar mitzvah, the question arose: On which arm should he lay his tefillin?

Rav Tuvia took his young son with him to pose this question to the venerated Posek HaDor, HaRav Moshe Feinstein, zt”l, who resided in the apartment directly above theirs.

Rabbi Goldstein vividly recalls what occurred during that visit. After listening to the she’eilah, Rav Moshe began to dissect the issue from every angle. After clarifying all aspects of the sugya, he concluded that in this situation, the bar mitzvah boy should lay tefillin on his right arm, in accordance with the opinion of the Vilna Gaon, since even though young Mordechai wrote with his right hand, that was not his natural way of writing, and he had had to be trained in order to write that way.

Over thirty years later, Rabbi Goldstein was talking in learning with the Posek HaDor, HaRav Yosef Shalom Elyashiv, zt"l. The topic under discussion was upon which arm an individual should place his tefillin if he writes with one hand but does all other melachos with the other. After clarifying all aspects of the sugya, Rav Elyashiv concluded that the halachahis in accordance with the minhag ha’olam brought by the Rema, that the writing hand is considered the primary hand.

“Well,” Rabbi Goldstein began, “what about someone like myself, who’s been laying tefillin on his right arm since his bar mitzvah, as per the Gra?”

“Perhaps it would be best for you to switch and begin to lay tefillin on your left hand,” Rav Elyashiv replied.

“But Rav Moshe told me to be noheg like the Gra,” Rabbi Goldstein said.

“Ahhh,” said Rav Elyashiv. “If Rav Moshe told you to do in this way, you should certainly continue to be noheg like the Gra.”

At the conclusion of the conversation, Rabbi Goldstein was already at the door when Rav Elyashiv suddenly called him back in. “Although I said to continue to do as you were told by Rav Moshe, nevertheless, toward the end of davening — after U'va L'tzion — it would be worthwhile for you to remove the shel yad from your right arm, without removing the shel rosh, and put it on your left arm for a few minutes to be mekayem the shitah of the Rema.” (Many who practice this stringency do not have a second shel yad and simply adjust the one they have for use on both arms. The tefillin is turned around so that the yud is on the inner side.)

Rabbi Goldstein followed HaRav Elyashiv’s advice, at the same time wondering if Rav Moshe would have had any objection to this added chumrah. It was likely he would never know since Rav Moshe was no longer here to ask ….

After many years of wondering, Rabbi Goldstein received the good tidings that there were people close to Rav Moshe who had been advised to put tefillin on both arms, due to the doubt regarding their status. A yungerman in Yerushalyaim who writes with his left hand and performs all other activities with his right hand was wondering if Rav Moshe was truly opposed to the idea of putting tefillin on the other arm. He called his uncle, Rabbi Avraham Pessin of Monsey, New York,a close talmid of Rav Moshe.

Rabbi Pessin related, “I myself asked Rav Moshe this question, and he told me that for a scrupulous individual it would be appropriate to put tefillin on both arms to fulfill the opinion of the Rema.”

HaRav Ephraim Greenblatt, the author of Teshuvos Rivevos Ephraim, also reports that although he himself never heard directly from Rav Moshe on the topic, he did hear from a rebbe in Mesivtha Tiferes Jerusalem, Rav Moshe’s yeshivah, that once, when discussing the she’ilah with Rav Moshe, the latter did indeed endorse the idea of a scrupulous individual putting the shel yad on the other arm as well.

It seems that the written teshuvah discourages the practice for young bar mitzvah bachruim and others who are not prepared to take on a stricter practice, but Rav Moshe did advise older, conscientious individuals to do so.

An important question must be raised for those who choose to put the second shel yad on the other arm at the end of davening. Must one remove — or move to the side — one’s tefillin shel rosh before taking off the shel yad to transfer it to the second arm?

One could argue that he must, because it is prohibited to wear the shel rosh without a shel yad. This is based on the Gemara that expounds on the pasuk, “V’hayu l’totafos bein einecha,” indicating that when a tefillin shel rosh is on one’s head, it should be the fulfillment of the complete mitzvah of tefillin — both the shel yad and the shel rosh, since “totafos” is in plural form.

However, many poskim rule that once the shel rosh is on one’s head, one need not remove it or move it off center in order to switch the shel yad from arm to arm. (This was an oral psak of both HaRav Elyashiv and HaRav Chaim Kanievsky. This would also seem to be the position of the Beur Halachah, although one can possibly differentiate between the two cases. The Aruch Hashulchan disagrees with this conclusion.)

In conclusion, there is clearly no obligation to change your present custom, and you definitely have every right to continue following the psak you originally received before your bar mitzvah. However, if you want to be extra-scrupulous in your fulfillment of the mitzvahof tefillin , many poskim recommend placing a shel yad on the other arm l’chumrah at a time when you feel you are ready for it.

The fulfillment of the mitzvah d’Oraisa of tefillin is predicated on wearing the shel yad on the correct arm. It is a very serious question that deserves careful deliberation and assessment of both the practical metzius and the correct direction of the halachah.

Comments powered by CComment