These verses just keep showing up through my readings.
I Chronicles 23 when David was working with the Levites it is written in verse 31
“and at the Sabbaths and on the New Moons and on the set feasts, by number according to the ordinance governing them, regularly before the Lord;
Then when one get into II Chronicles 2, Solomon is preparing to build the temple for the Lord. Verse 3 and 4 also shows these events.
3 Then Solomon sent to Hiram king of Tyre, saying:
As you have dealt with David my father, and sent him cedars to build himself a house to dwell in, so deal with me. 4 Behold, I am building a temple for the name of the Lord my God, to dedicate it to Him, to burn before Him sweet incense, for the continual showbread, for the burnt offerings morning and evening, on the Sabbaths, on the New Moons, and on the set feasts of the Lord our God. This is an ordinance forever in Israel.
Interesting that the Showbread is called continual. I know of others who say it was just upon the Sabbath, but this does not make it continual.
II Chronicles 8:12 – 13
12 Then Solomon offered burnt offerings to the Lord on the altar of the Lord which he had built before the vestibule, 13 according to the daily rate, offering according to the commandment of Moses, for the Sabbaths, the New Moons, and the three appointed yearly feasts—the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Tabernacles.
Nehemiah 10 they are restoring the Yahuwahs commands. Again here we see New Moon day being a separate day to Sabbath days and the set feasts.
32 Also we made ordinances for ourselves, to exact from ourselves yearly one-third of a shekel for the service of the house of our God: 33 for the showbread, for the regular grain offering, for the regular burnt offering of the Sabbaths, the New Moons, and the set feasts; for the holy things, for the sin offerings to make atonement for Israel, and all the work of the house of our God.