Yevamos - Daf 5
- The source for עשה דוחה לא תעשה according to the רבנן
The Gemara continues to look for a source, according to the Rabbanon, that an עשה is דוחה aלא תעשה , and attempts to learn it from a מצורע. The passuk states regarding the purification process “יגלח את כל שערו" – He shaves off all of his hair. A Baraisa asks why the Torah adds “את ראשו“– the hair on his head; obviously the hair on his head is included in כל שערו? It answers: לפי שנאמר "לא תקפו פאת ראשכם" – Because it states: “Do not cut off the payos of your head,” שומע אני אף מצורע כן – I would think that a מצורע too may not shave off his payos. Therefore, the words “את ראשו” – his head, teach us that a מצורע shaves off his payos as well. We see from this Baraisa that an עשה (the מצורע shaving his hair) is דוחה a לא תעשה (cutting off his payos). The Gemara eventually refutes this proof, as the לאו of לא תקפו is not שוה בכל, meaning, it does not apply equally to everyone, as women are not obligated in this. Therefore, we can only learn from a מצורע that an עשה is דוחה a לאו that is not שוה בכל – when it does not apply equally to everyone.
- שעטנז עד שיהא שוע טווי ונוז
The Gemara attempts to learn the source of עשה דוחה לא תעשה, according to the Rabbanon, from the word שעטנז. This word is superfluous, as the Torah could have just stated לא תלבש צמר ופשתים יחדו"“– Do not wear wool and linen together. Why did the Torah write לא תלבש שעטנז" " – Do not wear shatnez? It must be that it was intended for a derashah. The Gemara refutes this, saying that the word is indeed needed, to teach us עד שיהא שוע טווי ונוז – One is not chayav for wearing שעטנז unless it is smoothed, spun and woven (which is a contraction of the word שעטנז). Rashi explains that one is not chayav unless all three of these processes are done together. That is, one must combine unprocessed wool and linen together, comb them out together, spin them into a combined wool/linen thread and then weave the thread into a garment The Gemara concludes that we can learn both, שוע טווי ונוז, as well as עשה דוחה לא תעשה, from the word שעטנז. Being that the Torah used an extra word, we therefore use it for a derashah, and since the Torah used the unusual word שעטנז, instead of כלאים, we see that it is also meant to be used to teach that it must be שוע טווי ונוז.
- .Pesach, korban tamid and milah were before the giving of the Torah
The Gemara, in an attempt to find the source that an עשה is דוחה a לא תעשה שיש בו כרת, suggests that we can learn it from Milah, as it is permitted to do milah on Shabbos even though Shabbos is a לאו שיש בו כרת. The Gemara refutes this source, explaining that other מצוות cannot be learned from מילה, as מילה is a more important mitzvah, שכן נכרתו עליה שלש עשרה בריתות – as there were thirteen covenants sealed over it, which Rashi explains that the word ברית is mentioned thirteen times in the parshah of מילה. The Gemara then suggests that it be learnt from the korban Pesach, which may be done on Shabbos. The Gemara refutes this as well, as the korban Pesach is a more stringent עשה, in that not doing it carries a punishment of kares. The Gemara then attempts to learn from the עשה of korban tamid, which is done on Shabbos, but refutes this as well, as the korban tamid has a stringency in that it is brought every single day. The Gemara later says that we also cannot use a derashah of צד השוה and learn out from all three of these mitzvos together, as all three of these mitzvos were commanded before the giving of the Torah.
