WHAT IS CALLED MIKRA KODESH? [Mo'adim: Mikra Kodesh]
(Beraisa) Suggestion: Perhaps Yom Kipur applies only to one who fasted, and called it Mikra Kodesh and did not do Melachah!
Chagigah 18a (Beraisa - R. Yonason): A Kal va'Chomer forbids Melachah on Chol ha'Mo'ed. There is no Kedushah before and after the first and seventh days, yet Melachah is forbidden on them. There is Kedushah before and after Chol ha'Mo'ed, all the more so Melachah is forbidden on them!
This is unlike the six days of the week. Even though there is Kedushah (Shabbos) before and after them, Melachah is permitted on them, for there is no (Korban) Musaf. On Chol ha'Mo'ed, there is Musaf.
Question: Rosh Chodesh has Musaf, yet Melachah is permitted!
Answer: Rosh Chodesh is not called 'Mikra Kodesh'. We cannot learn from it to Chol ha'Mo'ed, which is called Mikra Kodesh.
Maseches Sofrim (19:1): On Pesach, in Tefilah and Kidush, one must mention 'b'Yom Tov Mikra Kodesh ha'Zeh.' On Chol ha'Mo'ed, one says 'b'Mo'ed Chag ha'Matzos ha'Zeh.'
Rambam (Hilchos Yom Tov 6:16): The Mitzvah of honor and Oneg on Shabbos applies also to Yom Tov, for it is called Mikra Kodesh.
Rambam (22): Chol ha'Mo'ed is called Mo'ed. Simchah is a Chiyuv.
Rambam (7:1): Even though Chol ha'Mo'ed is not called Shabboson, since it is called Mikra Kodesh and it is when Chagigah is brought in the Mikdash, it is forbidden to do Melachah.
Rosh (Hilchos Tefilin (after Menachos) 16): Rav Bartzeloni says in the name of a Ga'on that "v'Shomarta Es ha'Chukah ha'Zos" forbids Tefilin on Shabbos and Yom Tov. One should not rely on this, for the Halachah follows R. Akiva, who holds that Chukah discusses Pesach. We learn Shabbos and Yom Tov from "Lecha l'Os" (and Shabbos and Yom Tov themselves are an Os (sign that we are Hash-m's servants)). R. Yosi ha'Glili expounds "mi'Yamim", but not all days. This excludes Shabbos and Yom Tov, and surely also Chol ha'Mo'ed, which is called Mikra Kodesh. According to R. Akiva, who learns from "l'Os", Chol ha'Mo'ed is not included. Some wear Tefilin on Chol ha'Mo'ed without a Berachah. One who blesses does not lose.
Rashi (Shevuos 13a DH Lo Kar'o): Calling Yom Kipur a Mikra Kodesh is to bless Mekadesh Yisrael veha'Zmanim.
Rebuttal (Tosfos DH Lo): There is no Berachah mid'Oraisa of Yom Kipur! Rather, he admits that Beis Din was Mekadesh it, and refrains from Melachah due to Kedushas ha'Yom.
Ramban (Vayikra 23:2): The name Mikra Kodesh is because everyone is Keru'im (invited) and they gather to sanctify it. It is a Mitzvah for all of Yisrael to gather in Beis Hash-m (the Beis ha'Mikdash) on the day of the Mo'ed to openly be Mekadesh the day in prayer and Hallel to Hash-m.
Ohr Some'ach (Hilchos Teshuvah 1:1): If they did not bring the goats due to negligence, it is as if they did not call Yom Kipur a Mikra Kodesh, and it does not atone.
Shulchan Aruch (OC 188:7): If one omitted Ya'aleh v'Yavo in Birkas ha'Mazon on Chol ha'Mo'ed, he need not go back, for one need not eat bread.
Gra (7): Some disagree. It seems that they are correct. R. Eliezer says that one must eat 14 meals in the Sukah (Sukah 27a). Toras Kohanim expounds "Mikra Kodesh" - honor it with eating and drinking and clean clothing.
Mishnah Berurah (242:1): The Mitzvah of Oneg Shabbos is from Nevi'im - "v'Korasa l'Shabbos Oneg." Some say that its source is from the Torah, for Shabbos is included in Mikra'ei Kodesh, and we expound that we honor it through eating and drinking and clean clothing.
Shulchan Aruch (OC 487:1): In Shemoneh Esre of Pesach, we say "Es Yom Tov Mikra Kodesh ha'Zeh."
Beis Yosef (DH va'Titen): This is like it says in Maseches Sofrim. The Tur omitted it, for in Ashkenaz they do not say it. 'Yom Chag Ploni' already includes this. There is no reason to mention Mikra Kodesh more than the Isur Melachah or all Hilchos. Rav Hai Gaon says that they do not say it in Bavel. I say that the custom of Sefard is correct, for it is in Maseches Sofrim and no Tana or Amora disagrees. Mikra Kodesh shows that we must mention it in prayer, like the Ramban says. Perhaps we mention only what the Torah says. Mikra Kodesh implies that Melachah is forbidden. When the Torah mentions afterwards the Isur Melachah, this explains Mikra Kodesh.
Shulchan Aruch (490:3): On Chol ha'Mo'ed, we say 'Es Yom Mikra Kodesh ha'Zeh.'
Rema: Our custom is not to say 'Mikra Kodesh' on Yom Tov or Chol ha'Mo'ed.
Tur: Rav Hai Gaon was asked whether we say on Chol ha'Mo'ed in Ya'aleh v'Yavo 'b'Yom Chag Ploni ha'Zeh b'Yom Mikra Kodesh ha'Zeh.' He answered 'we say it only in Musaf. Some are meticulous not to say it in Musaf. They are wrong.' I (the Tur) see no difference between Ya'aleh v'Yavo and Musaf.
Beis Yosef (DH She'elah): Rav Hai Gaon holds that since Musaf is in place of Korban Musaf, which is to honor the Mo'ed, therefore, we mention it, just like on Yom Tov.
Bach (490:1): Here Rav Hai Gaon connotes that only on Chol ha'Mo'ed we do not say Mikra Kodesh in Ya'aleh v'Yavo, butwe say it on Yom Tov in Atah Vechartanu. In Siman 582, the Tur says in his name that we do not say it in Bavel. Here, the question was whether we say it in Ya'aleh v'Yavo on Yom Tov, and he answered 'we say only Es Yom Chag Ploni ha'Zeh.' Perhaps he meant that even on Yom Tov we do not say it in Atah Vechartanu.
Bach (DH u'Mah she'Chosav v'Eini): Rav Hai Gaon holds that Mikra Kodesh means that everyone is Keru'im and gather on the day for the Korban Musaf, therefore, we say this only in Musaf.
Birkei Yosef (2): On Chol ha'Mo'ed we do not say in Tefilah 'Yom Tov Mikra Kodesh', for one may do Melachah of Davar ha'Avud (there will be a loss if he does not do it). People might think that the same applies to Yom Tov if they were called the same
Shulchan Aruch (529:1): One must honor Yom Tov like Shabbos... and fix every meal on wine. Yom Tov clothing should be better than Shabbos clothing.
Shulchan Aruch (2): One is obligated to be happy on the Mo'ed, he and his wife, children and all his entourage. One gives parched and grain to children to make them rejoice; one buys nice clothing and ornaments for women according to his means.
Mishnah Berurah (16): The Rambam says that Chol ha'Mo'ed is called Mo'ed regarding Simchah. However, there is no obligation of honor and Oneg, for it is not called Mikra Kodesh.
Sha'ar ha'Tziyon (530:4): The Rambam (7:1) calls Chol ha'Mo'ed Mikra Kodesh, but in 6:16 he brings the Chiyuv of honor and Oneg due to to Mikra Kodesh only regarding Yom Tov. This is because there he discusses only Simchah. He holds that one need not be stringent about this on Chol ha'Mo'ed. Even though it is called Mikra Kodesh, since the Torah permits Melachah, at least for Davar ha'Avud according to everyone, it is not as Kadosh as Yom Tov. Therefore, also for honor it is not like Yom Tov. Even though the Mechilta obligates honoring it with eating and drinking and clean clothing, this means more than a Yom Chol, but we do not totally equate it to Yom Tov. Even though one opinion learns the Isur Melachah on Chol ha'Mo'ed from Mikra Kodesh, we permit Davar ha'Avud. This shows that it is lighter than Yom Tov. On Yom Tov one must eat bread, therefore one must repeat Birkas ha'Mazon if he forgot Ya'aleh v'Yavo, but not on Chol ha'Mo'ed. Likewise, one must honor Chol ha'Mo'ed with clean clothing more than a Yom Chol, but not as much as Yom Tov. The Magen Avraham (664:3) connotes that the custom is not to wear Shabbos clothing on Chol ha'Mo'ed, except for Hoshana Rabah. The Maharil was stringent for himself. However, it must be nicer than clothing of Yom Chol.
Gra (597:1): One may not fast on Rosh Hashanah because it is called Mikra Kodesh.