Study Guide Pesachim 63 A braita brings the opinion of acherim, attributed to Rabbi Meir, who holds that the order in which one says one is slaughtering the animal for those who are circumcised and those who are uncircumcised is important. If one begins with uncircumcised, it is invalid. This disagrees with the mishna. What is the root of the debate? The gemara brings 3 possible explanations and raises a difficulty with the second one. The mishna and gemara delve into the negative prohibition to have chametz in one’s possession when slaughtering a sacrifice. Which sacrifice- is it only the Paschal sacrifice or also the Tamid? What if one brought other sacrifices either on the 14th of Nissan on or Pesach and has chametz? Does the chametz need to be in the Temple to transgress the prohibition or even if it’s in one’s house? Rabbi Yochanan and Reish Lakish disagree about this and the gemara tries to figure out the source of the debate. The prohibition applies to the slaughterer, the kohen performing the rites and to all the people in the group who registered for that sacrifice.