Yes, Israel was set up as a Theocratic kingdom (and will be again when the Lord returns to sit upon David's throne, for the Millennium (Ps.2, 89, 2Sam.7:14, Isa,9:6-7 Rev.20).
The church (the organic body of believers (Rom.12,1Cor.12, Eph.1:23) is not Israel (1Cor.10:32).
This is dispensational theology. It differentiates between the Kingdom of Heaven (as offered in Matthew to the Jews) and the Kingdom of God as mentioned in Luke and Mark.
The Kingdom of Heaven is a literal physical kingdom (as Satan offered Christ in his temptation.)
The Kingdom of God is a spiritual kingdom (Rom.14:17).
The essential difference between Premillennial and Amillennial/Postmillennial is that a Premilleniast does not concern himself with the kingdoms of the world, knowing that things are going to get worse and worse until the Lord returns Himself and takes over (Rev.19).
All others seek to control the kingdoms of the world (both Protestant and Catholic) and thus must use some form of violence, since that is how these Kingdoms are controled (the Lord Himself will use great violence when He returns).
The differences on the nature of the church, the views of the millennium rule,('Pre'/'A'/'Post') the future role of Israel (will be given her unconditional promises made to her in the Old Testament) the differences between the Kingdom of Heaven and of God, all play a major role in determining how one views the combination of church and state.
The 'state' has a role to protect the decisions of those who want to advance the Kingdom of God (the spiritual kingdom) through peaceful exhortation of the Gospel and Scripture. The church however has no role in forcing anyone to accept that Kingdom or to maintain (as in Geneva) a certain level of 'orthodoxy'.
The best works to understand this system are the oldC.I. Scofield and the work 'Dispensational Truth' by Clarance Larkin.
But, but… If your main point was nothing needed outside teaching the scripture, why wouldn't proper teaching be limited to teaching how to memorize the Bible. And wouldn't Scofield and Larkin be extra-biblical, when did this dipensational tradition begin?
I'm not being critical of what you decide is your best understanding of your religious teaching. I am reiterating that it is a false distinction to claim to be different than those who follow the teaching of men and "tradition."
Lot's of stuff to disagree about as far as meaning, but "without tradition or teaching of men" is not something an organized church or theological system can exist.