R' Shimon ben Yehudah says in his name: The he-goats of Rosh Chodesh atone for a person who was tahor who ate a contaminat-ed [sacrifice]. Those of the Festivals surpass them in that they atone for a person who is tahor who ate a contaminated [sacrifice] and for one who had no awareness either in the beginning or at the end. Those of Yom Kippur surpass them in that they atone for a person who was tahor who ate a contaminated [sacrifice], and for one who had no awareness either in the beginning or at the end, and for one who had no awareness in the beginning but had awareness at the end. They said to him: May one be sacrificed for another? He said to them: Yes. They said to him: If so, those of Yom Kippur may be sacrificed on Rosh Chodesh, but how can those of Rosh Chodesh be sacrificed on Yom Kippur to effect an atonement which does not belong to them? He said to them: They all come to atone for the tumah of the Temple and its holy things.