Chullin Daf 141 צולין דַף 141

Rava says the word "תשלח" teaches that one must send away the mother bird even if he needs itלדבר מצוה – for the purpose of a mitzvah, e.g., to purify a מצורע. The Gemara objects that a passuk would seem unnecessary, because the עשה of the מצורע procedure cannot override the לאו and עשה violations of taking the mother bird from the nest (i.e., "לא תקח" and "תשלח")!? Mar bar Rav Ashi ultimately answers that the case is שנטלה על מנת לשלח – where he first took [the mother bird] intending to send it away, so he no longer violates the לאו. Therefore, perhaps the עשה of מצורע would override the עשה of שילוח הקן. The Gemara objects: מאי אולמיה דהאי עשה מהאי עשה – but what is the strength of this עשה (of מצורע) over that עשה (of שילוח), such that it should override it? It answers: we say גדול שלום שבין איש לאשתו – peace between a man and his wife is great, because Hashem’s Name, which was written in kedushah, is erased to bring about marital harmony (in the case of a sotah). Therefore, perhaps purifying a מצורע, who is forbidden to his wife until completing his purification, would override the עשה ofשילוח הקן.

The next Mishnah states: הנוטל אם על הבנים – if one takes a mother bird while it is on its young, Rebbe Yehudah says: לוקה ואינו משלח – he receives malkus, and does not send the mother bird away, but the Chochomim say: משלח ואינו לוקה – he sends away the mother bird, and does not receive malkus. They explain with a rule: כל מצות לא תעשה שיש בה קום עשה – any negative commandment which has in it a positive commandment to correct his transgression does not obligate malkus. Rebbe bar Mammal inquired about Rebbe Yehudah’s reasoning: does he hold לאו שניתק לעשה לוקין עליו – one always receives malkus for a לאו which is rectified by an עשה, disagreeing with the Mishnah’s rule? Or, does he agree that one does not receive malkus for a לאו שניתק לעשה, but says that this mitzvah is not a לאו הניתק לעשה, because he holds שלח מעיקרא משמע – the commandment to send away the mother bird implies to do so in the beginning only, not to correct a transgression of taking the mother bird from the nest? The latter explanation is eventually proven correct.

A Baraisa states that doves of a dovecote or a loft are subject to שילוח הקן, ואסורות משום גזל מפני דרכי שלום – but they are prohibited to others because of stealing, based on a Rabbinical enactment to promote harmony. The Gemara objects: according to Rebbe Yose bar Chanina’s ruling, thatחצרו של אדם קונה לו שלא מדעתו – a person’s chatzeir acquires for him without his knowledge, the eggs should be automatically acquired, and be exempt from שליחו הקן as "מזומן"!? Rav[a] answers: ביצה עם יציאת רובה הוא דאחייב בשלוח – an egg becomes obligated inשילוח  when its majority leaves the mother’s body, מקנא לא קני עד דתפול לחצרו – but is not acquired (by his חצר) until it falls into his courtyard. Since he did not yet acquire the egg, it is not considered מזומן. Alternatively, the Gemara explains that since Rav says it is forbidden to acquire the eggs while the mother is roosting on them, they are subject to שילוח even after falling into his chatzeir, because כל היכא דאיהו לא מצי זכי – wherever he cannot acquire the eggs because of a prohibition, חצרו נמי לא זכיא ליה – his chatzeir also does not acquire for him. [The Rabbinic prohibition against stealing is explained according to each interpretation.]