Yahweh is the author of HIS Holy-Days. He has given us instruction, direction and commands to observe (keep) and remember His Holy-Days. He also gave us the TIMES (days, weeks, and years) to observe His Holy-Days. These were given directly through His messengers who wrote the Law and the Prophets. You can search the scriptures all you want, but you will find no instruction ending or abolishing, or changing His mind about any of His Holy-Days.

Yahweh's Holy-Days can NOT be found on the counterfeit Roman calendar (see How Yahweh's Time Differs). They can ONLY be found on Yahweh's original calendar, instituted at creation (see Yahweh Created Time).

This makes it TRUE that, WHEN you worship and WHEN you celebrate determines WHO you worship.

Moses wrote in Leviticus 21 about Yahweh's Holy-Days. The first Holy-Day mentioned, the only one listed on the tables of stone, and the most frequently occurring is the Seventh-Day Sabbath - the rest repeating every seven days.

Leviticus 23:1-3
And Yahweh spake unto Moses, saying, Speak unto the children of Israel, and say unto them, Concerning the feasts of יהוה [Yahweh, our god], which ye shall proclaim to be holy convocations, even these are my feasts. Six days shall work be done: but the seventh day is the sabbath of rest, an holy convocation; ye shall do no work therein: it is the sabbath of Yahweh in all your dwellings.

This isn't Yahweh's ONLY Holy Day. Moses goes on to list Yahweh's other feasts and Holy Days. (see Feasts of Redemption)

But wait - who said these feasts are religious days? Can't feasts and holidays be secular? They can if you want, but that isn't Yahweh's plan.