Our Gemara continues its discussion about the pairs of chattas and olah brought by certain people. An even more specific subset of this group are those who bring a bird sin offering and a bird olah offering, it is a pair of birds, usually consecrated at the same time, known as a “keyn” or a “nest”.  This group includes a woman who gave birth, but is impoverished and cannot afford a lamb for the olah sacrifice, so she brings both chattas and olah from birds (Vayikra 12:8).  Likewise, a metzora who cannot afford an animal sacrifice (ibid, 14:22). Zav (ibid 15:14) and Zava (ibid, 15:29), and a “transgressor” (one who makes a false oath denying payment, as well as one who defiles something set aside as sacred for the Temple and uses it for personal use) who also cannot afford to bring an animal (Vayikra 5:7).  Finally, a Nazir who became exposed to a corpse brings a pair of birds, chattas and olah (Bamidbar 6:9-12).  

As we saw yesterday, the sin offerings of these persons involve sins that are ambiguous.  The bird sin offering represents even greater ambiguity (see Rosh Nedarim 83a), and sometimes it can even be brought when in doubt if obligated, which is never done with an animal chattas sin offering.  Rav Shimshon Rafael Hirsch (Vayikra 1:16) famously and poetically explains the symbolic plight of the bird sacrifice.  It is a vulnerable creature with few natural defenses other than to flee.  The specific rituals involved in the offering of the bird are demonstrative of its vulnerabilities and sudden brutalities.  It alone is slaughtered not by a ritual knife, but at the back of the neck with the cohen’s thumbnail, its body is torn, and blood squeezed out.  The message of the combined olah and chattas of birds seems to be one of vulnerability, specifically because the sin is not as clear.  In addition, many of the bird offerings are concessions to poverty.  The indigent have possibly half-way good excuses for their transgressions; after all, their personal circumstances are much more challenging.  The birds are to remind them of the vulnerability and the lack of clarity.

A final thought on this:  There is one other sacrifice that comes as a pair in the Torah, and that is the Scapegoat and the Sin offering of Yom Kippur.  They too have similar properties as the nest of the bird chattas and olah, in that they are bought as a pair and dedicated as a pair (Vayikra 16:8, see Mishna Negaim 14:5 and Yoma 62a).  The two birds and the two goats, both chosen seemingly randomly, meet a seemingly random fate. The message may be, though sometimes matters are morally ambiguous and you are not sure of how guilty you may be, think carefully, as Heaven and Hell are very close, depending on your decisions.