Yevamos Daf 34 יבמוס דַף 34

The Mishnah on Daf 33b taught that two men who accidentally exchanged wives under the chuppah, could be chayav up to four lavim each, which according to a Baraisa brought by Rebbe Chiya, would require them to bring four chatas offerings each. The Gemara here asks who is the Tanna who holds that two prohibitions take effect upon a single item whether it is through איסור כולל ואיסור מוסיף ואיסור בת אחת – a more inclusive prohibition, a more extensive prohibition or though two prohibitions that occur at the same time? Rav Yehudah said in the name of Rav that it is Rebbe Meir, for it was taught in a Mishnah: יש אוכל אכילה אחת וחייב עליה ארבע חטאות ואשם אחד – There is one who does one act of eating and is chayav four chatas offerings and one asham. The case is a tamei person, who ate cheilev, that was nossar, from consecrated offerings, on Yom Kippur. Rebbe Meir says that if it was Shabbos and he carried it out in his mouth before swallowing, he would be chayav a fifth offering. The Chochomim said to him, it is not in the same category, since the first list has to do with eating, and this was due to carrying. We see from here that Rebbe Meir holds of all three types of prohibitions, including an איסור בת אחת. 

The Gemara asks, who does Rebbe Meir rule in accordance with, given that he holds that the two men who accidently switched wives should bring chatas offerings? It cannot be according to Rebbe Yehoshua, for he holds טועה בדבר מצוה פטור – one who errs and sins while doing a mitzvah is patur. Rather, it must be Rebbe Eliezer, who holds טועה בדבר מצוה חייב – one who errs and sins while doing a mitzvah is chayav. Alternatively, it could be that he rules even in accordance with Rebbe Yehoshua, for Rebbe Yehoshua stated his position that a טועה בדבר מצוה פטור in the case of circumcising babies on Shabbos, דזמנו בהול – where a person’s time is rushed, since there is a mitzvah to circumcise the baby on the eighth day. If he erred in that situation and circumcised the wrong baby that was not meant to be circumcised on Shabbos, he is patur. But here, in the case of marrying the women, his time is not rushed, since there is no specific day that he must marry the women.

When Ravin came, he said in the name of Rebbe Yochanan: כל ששהתה אחר בעלה עשר שנים ונשאת שוב אינה יולדת – Any woman who waited after the death of her husband ten years and then remarries, can no longer bear children. Rav Nachman said: לא שנו אלא שאין דעתה להנשא – They did not teach this rule except when she did not plan on remarrying, but if she did plan on doing so, she can still become pregnant. Rava said to the daughter of Rav Chisda, his wife, whom he married ten years after her first husband, Rami bar Chama had died, and had then born children, that the Rabbis were whispering concerning you that you were unchaste during your widowhood. She said to him, אנא דעתאי עלך הואי – “My mind was on you,” meaning she was expecting to marry him. The Gemara in Bava Basra relates that one time, as a young child, she was sitting on Rav Chisda’s lap and both Rava and Rami bar Chama were there, and Rav Chisda asked her which one she would like to marry. She replied, “Both of them,” and she first married Rami bar Chama. After he passed away, she had her mind on Rava, but had to wait many years until Rava’s wife passed away. 

במתני' לעיל (דף לג, עמוד ב) שנים שהוחלפו נשותיהן כו' וחייב משום ד' לאווין, והכא הקשה הגמ', ומאן האי תנא דאית ליה איסור כולל ואיסור מוסיף ואיסור בת אחת, אמר רב יהודה אמר רב ר"מ היא דתניא יש אוכל אכילה אחת וחייב עליה ארבע חטאות ואשם אחד, טמא שאכל חלב, והוא נותר מן מוקדשין, ביוה"כ, ר' מאיר אומר אם היתה שבת והוציאו בפיו חייב, אמרו לו אינו מן השם

ור"מ אליבא דמאן, אי אליבא דרבי יהושע האמר טעה בדבר מצוה פטור, אלא אליבא דרבי אליעזר

איבעית אימא לעולם אליבא דרבי יהושע, כי קאמר רבי יהושע טעה בדבר מצוה פטור הנ"מ גבי תינוקות דזמנו בהול אבל האי כיון דאין זמנו בהול

כי אתא רבין א"ר יוחנן כל ששהתה אחר בעלה עשר שנים ונשאת שוב אינה יולדת

אמר רב נחמן לא שנו אלא שאין דעתה להנשא אבל דעתה להנשא מתעברת, אמר ליה רבא לבת רב חסדא קא מרנני רבנן אבתריך, אמרה ליה אנא דעתאי עלך הואי