Leviticus 23:24

23:24 “Tell the Israelites, ‘In the seventh month, on the first day of the month, you must have a complete rest, a memorial announced by loud horn blasts, a holy assembly.

Leviticus 23:39

23:39 “‘On the fifteenth day of the seventh month, when you gather in the produce of the land, you must celebrate a pilgrim festival of the Lord for seven days. On the first day is a complete rest and on the eighth day is complete rest.

Numbers 10:10

10:10 “Also in the time when you rejoice, such as on your appointed festivals or at the beginnings of your months, you must blow with your trumpets over your burnt offerings and over the sacrifices of your peace offerings, so that they may become a memorial for you before your God: I am the Lord your God.”

Psalms 81:1-4

Psalm 81

For the music director; according to the gittith style; by Asaph.

81:1 Shout for joy to God, our source of strength!

Shout out to the God of Jacob!

81:2 Sing a song and play the tambourine,

the pleasant sounding harp, and the ten-stringed instrument!

81:3 Sound the ram’s horn on the day of the new moon,

and on the day of the full moon when our festival begins.

81:4 For observing the festival is a requirement for Israel;

it is an ordinance given by the God of Jacob.

Isaiah 1:13-14

1:13 Do not bring any more meaningless offerings;

I consider your incense detestable!

You observe new moon festivals, Sabbaths, and convocations,

but I cannot tolerate sin-stained celebrations!

1:14 I hate your new moon festivals and assemblies;

they are a burden

that I am tired of carrying.