HEKDESH OF MECHUSAR ZEMAN [Mechusar Zeman:Hekdesh]
(Mishnah): One is exempt for Shechutei Chutz of Mechusar Zeman (a Korban not Kosher to be offered yet, e.g. an animal less than eight days old).
63b - Beraisa - Question: What is the source that one may not Makdish Mechusar Zeman?
Answer: "Umi'Yom ha'Shemini va'Hal'ah Yeratzeh l'Korban Isheh la'Shem".
Zevachim 112b (Mishnah - R. Shimon): One transgresses a Lav for (Hakravah of) Mechusar Zeman.
Bechoros 21b (Beraisa - R. Shimon): Mechusar Zeman enters the pen for Ma'aser. This is like the law of Bechor:
A Bechor becomes Kodesh (when it is born,) before it may be offered (on the eighth day). Likewise, Mechusar Zeman can get Kedushas Ma'aser, and it will be offered in the proper time.
Question: Why doesn't he learn from other Kodshim, which cannot become Kodesh before the proper time?
Temurah 19b (Beraisa): If a second year ram was brought for an Asham which must be a yearling, or vice-versa, it is Kosher, but the owner did not fulfill his obligation;
R. Shimon says, it is not Kodesh at all.
Question: But R. Shimon says that Mechusar Zeman gets Kedushas ha'Guf!
Answer #1: That is different, for it can be offered later.
Objection: If so, also a yearling Hukdash for a second-year Asham should get Kedushas ha'Guf!
Answer #2: Rather, R. Shimon learns Mechusar Zeman from Bechor:
(R. Shimon ben Yehudah citing R. Shimon): An animal before eight days enters the pen for Ma'aser even though it is Mechusar Zeman;
We learn from Bechor. It becomes Kodesh (at birth) before it can be offered, and it is offered in the proper time (after eight days. We do not learn to an Asham that is the wrong age, for there the animal is Kosher for different Korbanos.)
Parah (1:4): The following are Kesherim from day 30 and onwards: Chata'os and Olos of the Tzibur, Chatas Yachid, Asham Nazir and Asham Metzora. If any of these was offered from day eight and onwards it is Kosher. Nedarim and Nedavos, Bechor, Ma'aser and Pesach may be offered from day eight and onwards.
Rashi and Tosfos (Bechoros 21b DH Leilaf and DH Af): Kedushah does not take effect on Mechusar Zeman, except for Bechor and Ma'aser.
Question: R. Shimon is Mechayev a Lav for Mechusar Zeman. But in Bechoros the Gemara asks why he doesn't he learn Ma'aser from Kodshim (other than Bechor), regarding which a Mechusar Zeman cannot become Kodesh!
Answer (Tosfos Zevachim 114b DH Heter): It is forbidden to Makdish a Mechusar Zeman, but b'Di'eved it becomes Kodesh. (This is unlike Rashi and Tosfos above.)
Rambam (Hilchos Isurei Mizbe'ach 3:8): It is a Mitzvah to offer all Korbanos from the eighth day and onwards - "V'Hayah Shiv'as Yomim Tachas Imo umi'Yom ha'Shemini va'Hal'ah Yeratzeh". All seven days it is called Mechusar Zeman. Even though Mechusar Zeman is Pasul, one who transgressed and offered it is not lashed because it is a Lav derived from an Aseh.
Source (Radvaz): The Torah explicitly permits offering Bechor on the eighth day ("Uva'Yom ha'Shmini Titno Li"). Other Korbanos are clearly permitted after eight days - "Umi'Yom ha'Shemini va'Hal'ah Yeratzeh". Toras Kohanim (Emor Parshesa 8:5) learns each of them from the other, so all are permitted on the eighth day or afterwards.
Radvaz: This is regarding Nedarim and Nedavos, Bechor, Ma'aser and Pesach. Regarding obligatory Korbanos the ideal Mitzvah is from day 30 and onwards.
Rosh and Maharam me'Rotenburg (Parah 1:4): Chachamim require (l'Chatchilah) a bigger animal (at least 30 days) for obligatory Korbanos. Pesach is the exception, lest there will not be enough animals available. Also, Pesach is prone to become Nosar, since it may be eaten only by members of the Chaburah and only for one night.
Question (Mishneh l'Melech): If we know that an animal is not a Nefel (it had a full term pregnancy), may it be offered before eight days? The Torah forbids Hakravah before eight days because it is a Safek Nefel, just like a baby before 30 days. Why doesn't the Rambam discuss this?
Answer #1: A full term pregnancy proves viability for babies, but not regarding animals.
Rejection: Shabbos 136a permits to slaughter on Yom Tov a calf born that same day if it had a full term pregnancy.
Answer #2 (Mishneh l'Melech): It is a Gezeras ha'Kasuv that Korbanos may not be offered before eight days, even if it is not a Safek Nefel.
Question: If so, what is R. Shimon ben Gamliel's source that an animal is a Safek Nefel until eight days?
Answer #1 (Mishneh l'Melech): Indeed, the Torah forbids before eight days because it is usually Safek Nefel. The Torah forbids in every case, even when it is not a Safek.
R. Yom Tov Algasi (Hilchos Bechoros 1:14 DH v'Hinei Achti): The Torah does not allow Pidyon within 30 or eight days (for people and donkeys, respectively) because of Safek Nefel. Rashi (Shabbos 136a DH Lo Nitzrecha) says that we know that a pregnancy was full term only if the mother did not have relations the entire pregnancy. It is rare that we know this, therefore the Torah does not let us rely on it.
Answer #2 (Mishbetzos Zahav YD 15:3 DH Da): Reasoning teaches that it is a Safek Nefel before eight days.
Note: Presumably, he means that we have no source that it is viable, therefore it is a Safek to us. The Rashba (Bava Kama 11b DH Bechor) explains that it is a Gezeras ha'Kasuv to wait 30 days before Pidyon ha'Ben. It is not to preclude Safek Nefel. Nevertheless, we may infer that after this time it is viable, for the Torah would not command to redeem (or offer) a Safek Nefel.
Question (Mishneh l'Melech b'Sof, DH v'Lo): Why doesn't the Rambam bring the Isur to Makdish Mechusar Zeman? The Gemara (Zevachim 12a) says that one can make it Hekdesh on the eighth night, but it cannot be offered until the eighth day. This implies that it is forbidden to Makdish it beforehand! Tosfos (Zevachim 114b DH Heter) explicitly forbids this.
Mar'eh ha'Panim (Rosh Hashanah 1:1 (4a) DH Kan): The Rambam (3:10) says that Hekdesh of a Mechusar Zeman is like Hekdesh of an animal with a Mum that is Over (temporary), and one is not lashed for this. The Rambam (1:11) says that the only distinction between Hekdesh of a Ba'al Mum Kavu'a and of a Ba'al Mum Over is regarding their offspring. In both cases, the animal does not get Kedushas ha'Guf. Whenever the Gemara says that Hekdesh of Mechusar Zeman takes effect, this is like R. Shimon; Chachamim disagree. This is unlike Tosfos, who says that b'Di'eved Hekdesh of Mechusar Zeman takes effect.
Note: This is difficult, for the Rambam (1:11) equates Hekdesh of a Ba'al Mum Over and of a Tam, implying that it gets Kedushas ha'Guf!
Rambam (Hilchos Bechoros 6:15): One who buys animals is exempt from Ma'aser Behemah only if he bought them after they may be tithed. Therefore, if one bought lambs within seven days, when the time comes he must tithe them. Since Mechusar Zeman cannot be tithed, it is as if he bought fetuses and they were born when he owned them.