דַּבֵּ֛ר אֶל־בְּנֵ֥י יִשְׂרָאֵ֖ל לֵאמֹ֑ר בַּחֹ֨דֶשׁ הַשְּׁבִיעִ֜י בְּאֶחָ֣ד לַחֹ֗דֶשׁ יִהְיֶ֤ה לָכֶם֙ שַׁבָּת֔וֹן זִכְר֥וֹן תְּרוּעָ֖ה מִקְרָא־קֹֽדֶשׁ׃
"Fala aos Filhos de Yisrael, dizendo: No sétimo mês, no primeiro dia do mês, será para vós um descanso sabático, uma memória com som de trombeta, uma santa convocação.
Mishneh Torah, Rest
These six days on which Scripture prohibited labor—being the first and seventh days of Passover, the first and eighth days of Sukkot, the day of Shavuot and the first day of the seventh month (Rosh Hashanah)—are called holidays (yamim tovim). The [degree of] cessation of work is equal in all of them, in that all work is prohibited except for labor that is for the sake of eating—as it is stated (Exodus 12:16), "only anything that is eaten by any person."
Sefer Hamitzvot of Rasag
And the Shofar-blowing [holiday, i.e. Rosh Hashana] - to specify them for sanctity.