The word holiday is simply a mash of the two words: holy day. To see what days God/YHWH called holy in the Torah/Old Testament see your Bible concordance or do a search if you have a computer version of the Bible with study helps. E-sword is what I use and like. It's free yet they depend on donations to stay afloat so be generous. There are some free and not-so-free additions to the downloads for it. The only thing I have paid for other than my donation was a Bible version. Y