Today's daf is sponsored by Daniel and Eva Schweber, in loving memory of their father, Ken Schweber, who are learning daf yomi in honor of his own Talmud studies. And by Amy Goldstein in memory of her mother, Carolyn Barnett-Goldstein. "In honor of her 2nd Yahrtzeit, we miss her artistic spirit, wealth of knowledge, and joy for life."
If the animal for the Pesach sacrifice got lost and the original group divided into two and each group said to the other that if they found the animal or sacrificed another in its place, they should include the other in the slaughtering, if they both slaughtered and do not know who slaughtered first, no one can eat from the sacrifice and the whole animal is burned. And they are all exempt from Pesach Sheni. If they said nothing to each other, everyone fulfills their obligation with the animal they slaughtered and they can eat it. The gemara quotes a braita that concludes from this case that silence is preferable and quotes an verse from Proverbs to strengthen this claim. The mishna described a case in which the two Pesachs of two individuals got mixed up with each other. Each one will take one of the animals and bring someone else to join him and then will go with the other and stipulate, "If this one is my Pesach, then you will join with me and if this is not my Pesach, I will join with you." The Gemara discusses the connection between this mishna and the dispute between Rabbi Yossi and Rabbi Yehuda over whether one of the original members of the group must stay with the animal. The tenth chapter begins with a description of Passover eve - there is a prohibition to eat from close to the time of mincha. One needs to ensure that the poor people get four glasses of wine. Why did the mishna only talk about the prohibition of eat on the eve of Pesach and not mention all other erev Shabbats and Yom Tovs that also have a prohibition to eat from the time of the mincha. The gemara bring two answers - either the mishna is according to the opinion of Rabbi Yossi only, who holds that there is no prohibition to eat on erev Shabbats and holidays, only on Pesach because of the mitzva to eat matza or that there is a difference in the prohibitions - on the eve of Pesach is is a half hour before mincha and the others are from mincha. The gemara brings a braita that contradicts the second possibility, however Mar Zutra suggests that perhaps the braita is inaccurate.