Illustration Credit: Elad Lifshitz, Dov Abramson Studio
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Halakhah הֲלָכָה
Let’s say you enjoy doing a particular mitzvah and want to make it even better. Can you add on to it?
Actually, this could be a problem.
אֵת כָּל הַדָּבָר אֲשֶׁר אָנֹכִי מְצַוֶּה אֶתְכֶם אֹתוֹ תִשְׁמְרוּ לַעֲשׂוֹת לֹא תֹסֵף עָלָיו וְלֹא תִגְרַע מִמֶּנּוּ:
Everything I command you, you shall be careful to do.
Don’t add to it, or subtract from it.
This pasuk is the source for בַּל תּוֹסִיף (bal tosif), the principle that you’re not allowed to add onto mitzvot. Quoting a midrash, Rashi explains that the problem with bal tosif is when a person tries to add new components to an existing mitzvah.
For example:
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- I’m ready for Sukkot with my lulav, etrog, hadassim, and aravot. Now let’s throw in a lovely rose or two!
- The four פָּרָשִׁיּוֹת (parashiyot, sections) of Torah that are inside tefillin are inspiring. But how about adding a fifth? I can think of some fantastic Torah passages that could really enhance my tefillin.
- It’s such a shame בִּרְכַּת כֹּהֲנִים (Birkat Kohanim, the Priestly Blessing) is so short. I’d love to add some more pesukim to the blessing!
However, some people think the pasuk is actually a warning not to invent entirely new mitzvot that aren’t in the Torah.
How to know if it’s bal tosif
It’s bal tosif only if a person has כַּוָּנָה (kavvanah, inner intention) to fulfill a mitzvah while adding to it (Rosh Hashanah 28b). So, if you really like matzah, you can eat it throughout the year, as long as you don’t have the intention to be fulfilling the mitzvah of eating matzah—that’s just for on Pesah!
Adding to a mitzvah is not the same as repeating a mitzvah. So, it’s no problem to hear Kiddush multiple times on Shabbat, or to hear more shofar blasts than required on Rosh Hashanah (Tosafot on Rosh Hashanah 16b). For this reason, if you’re unsure about whether you did a mitzvah or not, it’s fine to repeat it without being worried about bal tosif.
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