Midrash su Levitico 23:2

1) (Vayikra 23:2) ("Speak to the children of Israel and say to them: The festivals of the L–rd, which you shall call (them) callings of holiness — these are My festivals.") And whence is it derived that the year is intercalated for the sake of those living in exile, (who left their places) and have not yet reached (Jerusalem for the festival)? From "the children of Israel … The festivals of the L–rd" — Arrange the festivals so that they can be observed by all of Israel.

1) Above (Vayikra 23:2), intercalation of the year is being spoken of, and here (Vayikra 22:4) sanctification of the month is being spoken of. If (the moon) were seen clearly, or witnesses came and testified (to that effect) before them (beth-din), and they were unable to proclaim "It is intercalated until it became dark — whence is it derived that it is intercalated? From "which you shall call (them) in their times." If you called them, they are My festivals. If not, they are not My festivals.

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2) If the year had to be intercalated, and they (beth-din) sat and deliberated and were unable to proclaim "It is intercalated" until the advent of Nissan, I might think that it were intercalated; it is, therefore, written "which you shall call them .. My festivals." If you call them, they are My festivals. If not, they are not My festivals.

3) If the year should not have been intercalated, and they intercalated it perforce or unwittingly or mistakenly — Whence is it derived that it is (nevertheless) intercalated? From (Vayikra 23:9) ("These are the festivals of the L–rd, callings of holiness, which you shall call (them) in their times": "them" — even unwittingly; "them" — even mistakenly; "them" — even perforce.

4) I might think that if they intercalated it at night, or one year for (purpose of) the next, for less than a month of for more than a month — I might think that it were intercalated; it is, therefore, written "them (only those halachically proclaimed) … these are My festivals," and not those.

5) And whence is it derived that the year is intercalated to answer some special need? From "which you shall call (them) in their times."

6) I might think that just as the year is intercalated to answer some special need, so, it is intercalated because of tumah (of the populace); it is, therefore, written (Vayikra 23:5) "In the first month … it is Pesach" — Let the first month not pass without Pesach.

(Numb. 29:35:) ON THE EIGHTH DAY YOU SHALL HAVE (literally: THERE SHALL BE FOR YOU) A SOLEMN ASSEMBLY. What is the meaning of FOR YOU? The Holy One said to Israel: The festive occasion⁵²Simhah. The allusion is to the solemn assembly on the eighth day of the festival, which is called Simhat Torah. is fitting FOR YOU; New Moons are fitting FOR YOU; festival times are fitting FOR YOU; holidays are fitting FOR YOU. It is therefore stated (ibid.): FOR YOU. A certain star worshiper questioned R. Aqiva. He said to him: Why do you keep festival times? Did not he say the following to you (in Is. 1:14): YOUR NEW MOONS AND YOUR FESTIVAL TIMES MY SOUL HATES? R. Aqiva said to him: If <the Holy One> had said: "My New Moons and my festival times my soul hates," I should have said so. He only said: YOUR NEW MOONS AND YOUR FESTIVAL TIMES, because these are the festival times which Jeroboam instituted, as stated (in I Kings 12:32): JEROBOAM ALSO INSTITUTED A FESTIVAL…. These festival times, however, (the ones ordained by the Holy One) shall never be abolished. Neither shall the New Moons. Why? Because they belong to the Holy One, as stated (in Lev. 23:2): THE FESTIVAL TIMES OF THE LORD. It also says (ibid.): THESE ARE MY FESTIVAL TIMES. [(Also in vs. 4:) THESE ARE THE FESTIVAL TIMES OF THE LORD.] They shall, therefore, never be abolished; for it is concerning them that it is stated (in Ps. 111:8): THEY ARE ESTABLISHED FOREVER TO BE PERFORMED WITH FAITHFULNESS AND UPRIGHTNESS.

26 (Numb. 29:35) “On the eighth day”: What was the reason for [the number of sacrificial animals] being reduced on each day? The Torah is simply teaching you etiquette from the sacrifices. Thus if someone goes for lodging,²²Gk.: Xenia. and his host receives him; on the first day he receives him properly and feeds him fowl. Then on the second he feeds him meat; on the third he feeds him fish; on the fourth he feeds him greens. So does he continue to reduce, until he is feeding him pulse. (Numb. 29:35) “You shall have (literally, there shall be for you)”: What is the meaning of “for you?” [The Holy One, blessed be He,] said to them, “Festival times are fitting for you.” A certain gentile questioned R. Aqiva. He said to him, “Why do you keep festival times? Did not the Holy One, blessed be He, say the following to you (in Is. 1:14), ‘Your new moons and your festival times My soul hates?’” R. Aqiva said to him, “If He had said, ‘My new moons and My festival times My soul hates,’ I should have said [so. But] He said, ‘Your new moons and your festival times’; because of those festival times which Jeroboam instituted, as stated (in I Kings 12:32-33), ‘Jeroboam also instituted a festival on the fifteenth day of the eighth month, like the festival in Judah, at Bethel to sacrifice to the calves. And he ascended the altar […] and he made a festival for the Children of Israel […].’ These festival times, however, (the ones ordained by the Holy One, blessed be He,) shall never be abolished. Neither shall the new moons. Why? Because they belong to the Holy One, blessed be He, as stated (in Lev. 23:37), ‘These are the festival times of the Lord.’ And similarly (in Lev. 23:4), ‘These are My festivals times.’” And it is also written (ibid. verse 44), “And Moses told the festival times of the Lord.” They shall, therefore, never be abolished; for it is concerning them that it is stated (in Ps. 111:8), “They are established forever to be performed with faithfulness and uprightness.”