The Mishna in Pesachim 35a lists all the things that one can’t
use to fulfill their obligation of
matzah.
Included on the list is
tevel. The Gemorah 35b explains it isn’t good
for the
mitzah because one can only fulfill the obligation it the
issur
of
chametz would apply to it as opposed to what is prohibited because
of
tevel and this rule is based upon a
derasha.
The Gemorah explains that the
ברייתא that gives this
explanation holds
אין איסור
חל על איסור and hence because there is a prohibition of
tevel the
prohibition of
chametz doesn’t take effect.
Presumably, since we hold
איסור חל על איסור באיסור מוסיף
it should come out that you can fulfill your obligation with
tevel.
However, the Rif and Rambam rule that you can’t
fulfill your obligation.
Why?
The Rishonim explain because of the principle
of
מצוה הבא בעבירה.
If this understanding is correct, why didn’t
the Gemorah give this reason and why do we need a specific
derasha here
if there is a general
pesul?
Tosfos
Sukkah 9a says that the rule of
מצוה
הבא בעבירה is only a Rabbinic
pesul and the Gemorah is giving an
explanation that will make it a Torah
pesul.
Another answer the Rishonim cite in the name of Tosfos (cited
in Rabbenu Peretz here) suggest that the only time we find the pesul of מצוה הבא בעבירה
is regarding mitzvot that come to be מרצה such as korbanot, lulav (has
an aspect of prayer and hallel to it.)
However, matzah that isn’t coming to be מרצה there is no pesul of מצוה הבא בעבירה. The Rishonim ask questions on this interpretation
from examples of מצוה
הבא בעבירה even when the mitzvah isn’t
coming לרצות. (According to this interpretation it should
come out we don’t hold there is מצוה
הבא בעבירה in this case.)
The Ramban entertains a possibility that there is no problem
of מצוה הבא בעבירה
here because the person has the ability to fix the issur by separating the
proper tithes. What is the explanation
of this sevarah, what does it help that you could remove the issur,
right now it is assur? The
Achronim explain the yesod of the pesul מצוה הבא בעבירה is that the חפצא
is a חפצא
of averah. Regarding tevel what
defines it as a חפצא
של עבירה isn’t because of the averah done to it, there was no averah
done to it, rather it is defined that way because the מצוה is
performed via an averah. The Ramban
holds if one can avoid the issur by tithing, it isn’t considered as if
the averah is enhancing the mitzvah because it can be avoided.
It is interesting to note that Rashi on the Mishna explains
the pesul based upon a suggestion of the Gemorah that the ברייתא could even fit with
the Rabbis that it comes to exclude anything that has an issur besides
that of chametz alone. The
Gemorah rejects this explanation because there is no mention of “only” in the ברייתא. So why does Rashi cite a rejected pshat?
However, the Meiri
says that the rejection of the Gemorah is merely a דחוי but really that answer stands. This would be a different explanation as to
why we would rule that you can’t fulfill your explanation and we don’t have to
come up with a new reason of מצוה
הבא בעבירה (see Birchat Mordechai Pesachim #19.)
