New moons appear among the festival sacrifices in Numbers (28:1–29:39), but not among Leviticus’s appointed times (23:1–44). Why?

Perhaps Leviticus lists only holy convocations forbidding work, whereas new moons permit work. Yet it also mentions days that are not holy convocations, such as waving the omer and the days between festival convocations.

Moreover, unrestricted new-moon work is not obvious. Although the Torah explicitly gives no prohibition, other biblical passages show it as a significant occasion for large feasts (I Samuel 20:18–42), apparently with some cessation of work: “When will the new moon be gone, that we may sell grain? and the sabbath, that we may set forth corn?” (Amos 8:5). Its additional offering, two bulls, one ram, and seven yearling lambs (Numbers 28:11), identical to Passover and Shavuot, likewise suggests a sacred day similar to festivals.

I propose another explanation: the Torah distinguishes two kinds of appointed times:

  1. The LORD’s appointed times, belonging to Him.
  2. Israel’s appointed times, belonging to Israel.

Leviticus lists only the former: “These are the appointed seasons of the LORD, even holy convocations, which ye shall proclaim in their appointed season” (Leviticus 23:4). Other times of celebration belong to Israel rather than this category. New moons are such occasions; despite special offerings and importance, they are absent from the LORD’s list in Leviticus and present in Numbers’ sacrificial list.

Every Torah reference presents new moons as Israel’s. Numbers calls them “And in the beginnings of your months” (Numbers 28:11), your new moons.

They appear once more with the silver trumpets:

Also in the day of your gladness, and in your appointed seasons, and in your new moons, ye shall blow with the trumpets over your burnt-offerings, and over the sacrifices of your peace-offerings; and they shall be to you for a memorial before your God: I am the LORD your God.’ (Numbers 10:10)

וּבְיוֹם שִׂמְחַתְכֶם וּבְמוֹעֲדֵיכֶם וּבְרָאשֵׁי חָדְשֵׁיכֶם, וּתְקַעְתֶּם בַּחֲצֹצְרֹת עַל עֹלֹתֵיכֶם וְעַל זִבְחֵי שַׁלְמֵיכֶם, וְהָיוּ לָכֶם לְזִכָּרוֹן לִפְנֵי אֱלֹהֵיכֶם – אֲנִי, ה' אֱלֹהֵיכֶם. (במדבר י', י)

Here too they are “your new moons,” alongside “the day of your gladness, and … your appointed seasons,” days belonging to Israel rather than the LORD’s appointed times.

This explains the special need to sound trumpets on new moons: to bring a national occasion into religious awareness and remembrance before the LORD, since it lacks the LORD’s festivals’ inherent religious standing.