1) THE UNIQUE ASPECT OF AN "ASHAM METZORA"
QUESTIONS: The Gemara states that the Torah writes an extra verse to teach that a Korban Asham Metzora, like a Chatas, requires Matan Damim, and requires that its Eimurin be burned on the Mizbe'ach. One might have thought that an Asham Metzora differs from other Korbanos, since it requires Zerikah on the right large toe, thumb, and ear of the Metzora, and thus perhaps the Zerikah distinguishes the laws of Asham Metzora from the laws of other Korbanos. The Torah therefore teaches that it indeed requires Haktaras Eimurin like other Korbanos.
TOSFOS (DH Lefi) quotes RABEINU YAKOV of Orleans who asks why the Gemara does not mention another significant difference between an Asham Metzora and other Ashamos. An Asham Metzora requires Nesachim, in contrast to other Ashamos. Why does the Gemara not mention this reason to distinguish between an Asham Metzora and other Korbanos?
ANSWER: TOSFOS answers that in order to distinguish something as "different" in its category (in this case, Asham Metzora among Korbanos), it must have not only different aspects, but contradictory aspects, from other things in its class. The fact that an Asham Metzora (see KEREN ORAH at length in order to understand why Tosfos mentions Chatas here instead of Asham, although the SHITAH MEKUBETZES implies that Tosfos actually wrote "Asham" as well and just added the word "Chatas") has Nesachim is an additional aspect of the Asham, but is not something that gives sufficient reason to assume that its other Halachos should different from those of an ordinary Asham. The difference which the Gemara mentions is that the Torah says that the blood of an ordinary Asham is sprinkled on the Mizbe'ach, but with regard to an Asham Metzora the Torah mentions only that its blood is sprinkled on the Metzora. This implies that it is not sprinkled on the Mizbe'ach. The Torah therefore must teach that it indeed requires Zerikah on the Mizbe'ach as well. (Y. MONTROSE)
2) WHY DOES THE GEMARA ASK ITS QUESTION A SECOND TIME, AND GIVE A DIFFERENT ANSWER?
QUESTION: The Gemara asks that the requirement to bring the Yoseres and Kelayos of the Par He'elem Davar to the Mizbe'ach should have been written in the verses of the Par He'elem Davar itself. Why does this Halachah need to be derived from a different source?
TOSFOS (DH v'Nichtevei b'Gufei) asks that this question was already asked and answered by the Gemara earlier (41b). The Gemara there asks, why is the requirement to bring the Yoseres and Kelayos of the Par He'elem Davar to the Mizbe'ach derived from the Par Kohen Mashi'ach and is not written in the verses of the Par He'elem Davar itself? The Gemara there answers that it is comparable to a king who loved one of his friends. When his friend sinned, the king reduced the amount of scorn that his friend deserved, due to their friendship. Similarly, when the Torah describes the laws of what must be done when the Jewish people sin, it does so as briefly as possible, even omitting some of the essential details if they can be derived from other places.
Why does the Gemara here ask this question again, and give a different answer?
ANSWER: TOSFOS answers that the primary reason why the Torah does not write this Halachah in the verses of the Par He'elem Davar is that it wants to teach, as the Gemara here says, that a law which is derived through a Hekesh cannot be applied to another topic through a second Hekesh.
Why, then, does the Gemara earlier (41b) not give this answer, but instead answers that the reason this law is not stated in the verses of the Par He'elem Davar is that Hash-m, out of his love for the Jewish people, sought to abbreviate the discussion of the Halachic process of the Par He'elem Davar?
Tosfos (as explained by the BIRKAS HA'ZEVACH) explains that the rule that a law which is derived through a Hekesh cannot be applied to another topic through a second Hekesh is a general rule which the Torah could have taught using any subject in the Torah. The fact that the Hash-m specifically chose to teach this lesson by omitting some of the laws of the Par He'elem Davar was solely out of His love for the Jewish people. (Y. MONTROSE)