The previous mishnah dealt with a Pesach offering that became mixed up with other offerings. Our mishnah deals with a case in which a person does not know at all whether he was registered for a particular Pesach offering, and which of the offerings was slaughtered on his behalf.
The first case - the group appointed the agent:
"Chavurah she'avad pischah, ve'amru le'echad: tzei uvakesh ushechot aleinu" - a group that was registered for a particular Pesach offering and their animal was lost, and they told one of the members of the group to go out and search for the lost Pesach offering and slaughter it on their behalf. "Vehalach umatza veshachat, vehen lakchu veshachtu" - the agent went out, found the original animal and slaughtered it; meanwhile the members of the group, who were concerned that he might not find it, took another animal and slaughtered it. They did not include the agent in the new Pesach offering, since he had never asked them to register him for it.
"Im shelo nishchat rishon" - he eats from his own, from the original Pesach offering that he found, and they eat with him from his, since this is the offering for which they were registered from the outset; and the second Pesach offering that they made is invalid and is not put to use.
"Ve'im shelahen nishchat rishon" - they eat from theirs, from the new Pesach offering, since by slaughtering it they withdrew from the original offering; and he eats from his own, from the original Pesach offering.
"Ve'im eino yadua eizeh mehen nishchat rishon", or if both were slaughtered at the same moment - he eats from his own, since he is certainly not registered for their offering, because they never registered him for it, and he must therefore be registered for the original offering. But they do not eat with him, since perhaps they are registered for their own offering which was slaughtered first, and the matter is unknown.
"Veshelahen yatza leveis hasereifah" - their new Pesach offering is burned, since perhaps they were in fact registered for the original offering, and if so they may not eat from the second one either, and no one can eat it. The first offering, by contrast, is eaten at least by the agent.
"Upturin mila'asos Pesach sheni" - nevertheless they are exempt from the second Pesach, since they were certainly registered for a Pesach offering; the only doubt is whether it was for the first or the second, but the fact of the registration itself is certain, and therefore they are not required to bring a second Pesach offering.
The second case - the agent registered himself with the group:
What is the law if that person who was sent to search for the original Pesach offering said to them: "If I am delayed, go out and slaughter on my behalf," while they asked nothing of him. This time, unlike the first case, it was he who asked to be included in the new Pesach offering. He went out, found the original offering and slaughtered it, and they brought a new animal and slaughtered it:
Theirs was slaughtered first - they eat from their new Pesach offering, and he eats with them, since he asked to be registered for it.
His was slaughtered first - he eats from his own, from the original Pesach offering, and they eat from theirs; for in this case they did not ask him to slaughter on their behalf, unlike the first case, where they told him, "Slaughter the original Pesach offering on our behalf if you find it." Here they made no such request at all, but rather he alone said to them, "If I am delayed, slaughter on my behalf" - and the roles are reversed.
It is unknown which was slaughtered first, or both were slaughtered at the same moment - they eat from theirs and not from his, and he does not eat with them, since perhaps he was not registered for theirs but rather for his own. He cannot eat from his own either, since perhaps he was registered for theirs, and therefore his Pesach offering goes out to the place of burning. Nevertheless, he is exempt from bringing a second Pesach offering, since he was certainly registered for one of the two offerings.
The third case - they registered one another:
They said to him, "Find the first Pesach offering and slaughter it on our behalf," and he said to them, "If I do not arrive in time, slaughter on my behalf." In this case they all eat from the offering that was slaughtered first. And if it is unknown which of them was slaughtered first, both go out to the place of burning, since no one can eat from them. Here too they are exempt from bringing a second Pesach offering, since they were certainly registered for the offering that was slaughtered first, only that it is unknown which one it is.
The fourth case - they did not register one another:
If neither of them registered the other, there is no mutual responsibility between them at all. Each one stands on his own with regard to his own Pesach offering, and they have no connection with one another.