Kinnim, Chapter 2, Mishnah 5. Our chapter has been following birds that fly from one set to another and asking which of them may still be brought on the mizbeach. This mishnah opens with one more arrangement of that kind, and then turns to an entirely new subject: the requirement that a person's pair of birds come from a single species.
A designated chatat on one side, a designated olah on the other
"Chatat mikan ve'olah mikan u'stumah ba'emtza": a person has a bird already designated as a chatat standing on one side, a bird already designated as an olah standing on the other side, and in between the two of them sits a pair that was never designated at all, one bird of which will eventually serve as a chatat and one as an olah.
"Parach min ha'emtza litzdadim, echad halach ve'echad halach": the two undesignated birds fly out of the middle, one of them joining the designated chatat and the other joining the designated olah. Each side now holds two birds, and we cannot tell which of the two is the one that was designated and which is the newcomer. Still, one thing is certain: on the right side, one of the birds is unquestionably a chatat, and on the left side, one of them is unquestionably an olah. Alongside each of them stands a bird that carries no designation whatsoever.
The verdict here is "lo hifsid kelum": nothing whatsoever has gone to waste, and every bird in this picture remains fit for the mizbeach. "Ela yomar": the owner has only to make a declaration. "Zeh shehalach etzel chata'ot chatat" - the bird without a designation that flew over to the chatat side is hereby brought as a chatat; "vezeh shehalach etzel olot olah" - and the one that flew over to the olah side is hereby brought as an olah. A bird that carries no designation can be steered toward either offering, so this arrangement leaves not even a shade of doubt.
When a bird returns to the middle
"Chazar la'emtza": now a bird from each side flies back into the middle. The two birds sitting in the center might each be one of the original undesignated birds, or one of them might be the designated chatat and the other the designated olah, or any combination of these. "Ha'emtza'iyim yamutu", the birds in the middle are left to die, exactly as we rule whenever a chatat and an olah have become indistinguishable from one another.
The birds that stayed put on either side, by contrast, are in no difficulty: "eilu yikrevu chata'ot ve'eilu yikrevu olot". Whatever bird is left standing on the chatat side goes up for a chatat, and whatever is left on the olah side goes up for an olah. It makes no difference which of the two it turns out to be: if it is the originally designated bird, it is already in its proper place, and if it is the undeclared partner, it can be directed toward that offering at will. The tangle is confined to the center, where one bird arrived from the right and one from the left, each of them possibly a chatat and possibly an olah, so neither can go up on the mizbeach.
The mishnah continues: "Chazar o sheparach" - if one of the central birds now travels back out "min ha'emtza litzdadim", from the middle toward the sides - then "harei kulan yamutu". Once a bird from the center settles on a side, that side may be holding a bird whose true status is the reverse of what belongs there, and no declaration can straighten it out any longer. Every one of the birds is therefore left to die, in keeping with the standing rule that a chatat and an olah mingled past recovery are both lost.
Doves and pigeons may not be paired
Until now we have been dealing with mixtures of designated and undesignated birds. The mishnah now moves to a different question entirely: which species may be joined together in a single obligation. Only two kinds of birds are fit for the mizbeach, a tor (a dove) and a ben yonah (a pigeon).
"Ein mevi'in torin keneged benei yonah velo benei yonah keneged torin": a tor may not be set opposite a ben yonah, nor a ben yonah opposite a tor. Each species is entirely fit for the mizbeach on its own, yet the pair that a person owes has to be drawn from one kind alone. The chatat and the olah must match each other in species, and an obligation cannot be filled half from the one kind and half from the other.
"Keitzad?" The mishnah illustrates: "Ha'ishah shehevi'ah chatatah tor ve'olatah bat yonah, tachzor vetavi olatah tor." A woman who owes a pair of birds offered a tor for her chatat and a ben yonah for her olah. Because the two are not of one species, her obligation stands unfulfilled and needs repair. Which route does she take: add a tor for the olah, or add a ben yonah for the chatat? The mishnah answers that she goes back and offers a tor as her olah. The chatat is what determines the species of the whole obligation, and since her chatat was a tor, her olah must be a tor as well.
"Olatah tor vechatatah bat yonah, tachzor vetavi olatah bat yonah." Here the order was reversed: she brought the dove first as her olah, and only afterward brought the pigeon as her chatat. Even so, she must bring a pigeon as her olah. The chatat, though it came second, is what establishes the species through which her obligation will be fulfilled, so it is the pigeon that sets the standard and a pigeon olah that completes the pair.
"Ben Azzai omer": his position is "holchin achar harishon", that we follow whichever bird came first rather than the chatat. Where the chatat happened to be the opening offering, the two opinions coincide, and she completes the pair with an olah of that same species. But where the olah was offered first from one kind and a chatat of the other kind followed it, Ben Azzai has her round out the obligation with a chatat matching that opening olah, notwithstanding the chatat she has already offered. In his view the korban that inaugurates the obligation is the one that fixes its species.
When the woman dies before completing the pair
"Ha'ishah shehevi'ah chatatah umetah, yavi'u hayorshin olatah." A woman obligated in a pair of birds brought her chatat and then died before her olah was offered. Her heirs do bring the olah on her behalf. An olah is in the nature of a gift to Hashem, and there is no objection to such a gift being offered for a person after death.
"Olatah umetah" - if the olah was offered and she died while the chatat was still outstanding - then "lo yavi'u hayorshin chatatah", the heirs do not offer it. A chatat exists in order to bring atonement, and once a person is no longer among the living, there is no atonement left to secure for her.