Why does the Torah insert the (otherwise superfluous) words "asher Yevukar la'Hashem"?
What is "Ach" coming to preclude?
Temurah, 25a: It precludes other Kodshim from the D'rashah in 27:26:0.1:1 - and the prohibition against declaring a Kodshim animal as a different form of Hekdesh applies even whilst it is a fetus in its mother's womb. 1
See Torah Tm imah, note 146.
What does the Torah mean when it writes about a firstborn animal "Lo Yakdish"?
Rashi and Rashbam: It means that one is not permitted to take a B'chor and declare it Hekdesh (as an Olah or a Shelamim), since it is not his 1 (to declare Hekdesh).
Ramban and Moshav Zekenim: The Torah means (not that one may not declare it a B'chor, but) that one need not do so. 2
How will we reconcile the current Pasuk ("Lo Yakdish") with the Pasuk in Devarim, 15:19, which states "Kol ha'Bechor ... Takdish la'Hashem Elokecha"!
Rashi #1 (in Re'ei Devarim, 15:19): Although a B'chor is automatically Kadosh, it is nevertheless a Mitzvah for the owner to declare it Hekdesh 1 .
Rashi #2 (Devarim 15:19): Although one cannot sanctify the actual B'chor as another Korban, 2 one can however, declare Hekdesh his Tovas Hana'ah, 3 and he must give that amount to Hekdesh. 4
Ramban: What the Pasuk in Devarim means is that one should treat it as Hekdesh, not to work with it or to shear it, and to eat it in Yerushalayim.
This can perhaps be compared to the Mitzvah to add fire to the Mizbe'ach, even though fire comes down from Heaven.
See Torah Temimah, note 149
Rashi (Bechoros 53b): This is the amount that another Yisrael would pay him on condition that he gives it to [a Kohen that the latter chooses, e.g] his grandson.
See Torah Temimah, note 150
?Ach B?chor ? bi?Veheimah, Lo Yakdish Ish oso ? la?Hashem hu?. Why does the Torah insert the (otherwise superfluous) words "bi'Veheimah" and "Lo Yakdish Ish oso"?
Temurah, 25a: Because, had it not inserted " Ish oso" the Pasuk would imply that a firstborn is not eligible to declare Hekdesh, and had it omitted "bi'Veheimah", it would have implied that he cannot be Makdish a B'chor but others can. Therefore the Torah inserts "bi'Veheimah" to teach us the "B'chor is referring to B'chor Beheomah and not B'chor Adam.
