Menachot 37 - The Tefillin of a Lefty

The arm tefillin must be worn on the weaker arm, since the commandment is to "bind it on your arm" (yadchah), which may be read as "yad kah"- the weaker arm. There are many opinions as to how an amputee wears his tefillin. Tosafot say that one who is completely missing his left arm does not wear the tefillin at all, one who is missing the lower portion of his left arm dons tefillin on his stump, and one who is missing the lower portion of the right arm is considered a lefty and dons tefillin on his right stump.

About a left-handed person, some say that he dons tefillin on his right arm, which is his weaker one, but others claim that since most people are right-handed, he too dons tefillin like them, that is, on his left arm.

Plimo asked Rabbi Yehudah the Prince a question, "One with two heads, on which of them does he don tefillin?" Rabbi Yehudah was indignant. At this moment a man came in and said, "A child with two heads was born to my wife. How much money do I need to pay to a kohen to redeem the child?" Elijah the Prophet came and gave an answer: "Ten coins, twice the amount, since the Torah counted people by the head."

Art: Federico Zuccaro - Study Of Two Heads

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