Was the decalogue intended for everyone, and the other 600 some-odd commandments meant only for Levites?
No, the 10 Words, or 10 Commandments, or Decalogue as you are calling it, is just a general outline. The rest of the Torah parses out who does what. If you remember, God tells the leaders of Israel, speak to the sons of Israel before he establishes certain things, this means it is for all of the people designated in the passage. Also, keep in mind that the words ‘alien’, foreigners, or sojourners speak to those Gentiles who follow the God of Israel. These would apply to what we call today, “Christians” if they claim to follow Jesus (Matt. 5:17–19, ESV)
Cheryl Durham, Ph.D.
Cheryl is the Executive Director at Living Truth. She is also currently Dean of Students and Professor of New Testament Culture and History at Master's International University of Divinity. She holds a Bachelor and Master's Degree in Biblical Counseling, a Doctor of Biblical Studies in Worldview and a Ph.D. in New Testament History and Culture.