I'm a member of a discussion group and someone in that group noted, offhand, that "the majority of Christians [fall] into two camps: those who believe that 'whatever is not expressly prohibited, is permitted' (Luther) and those who believe that 'whatever is not expressly permitted, is prohibited' (Zwingli)."
I had never heard anyone express such a view before, but it seems to "explain" a whole lot that has puzzled me.
No one, as I grew up, ever discussed the two possibilities. My sense, however: I was raised with a more "Lutheran" view, a view paralleled, it seems, in my mind, by Jesus' comment to his disciples: "whoever is not against us is for us" (Mark 9:40) or "whoever is not against you is for you" (Luke 9:50).
But when I got to seminary--and after, as I dealt with more "Reformed" Christians (Calvinists . . . or Zwinglians)--I bumped into the latter view, a view paralleled, it seems, in my mind, by Jesus' comment to his disciples: "He who is not with me is against me, and he who does not gather with me scatters" (Matthew 12:30; Luke 11:23).
I'm not prepared, here, to go in-depth into the issues, but you can see some of these differences at work in such matters as the "regulatory principle" in worship and--which most of us who have not been raised in such circles see as a different issue--holiday observances.
You can find some of the most outspoken presentations on this matter of the regulatory principle at the Still Water Revival Books website and, most particularly (among many), at their "Against Pagan and Roman Catholic Holy Days (Holidays) Like Christmas and Easter" page. Quite shocking.
A sample of the kind of material you will find there: the following summary of Christmass Condemned by Christ, a sermon by Greg Price:
I'm afraid I'm out of time to comment further at this point. I hope to return to this subject shortly.Price shows how the teaching of the Lord Jesus Christ condemns all man-invented holy days. Scripture and history are brought to bear most specifically on the celebration of Christ-mass, demonstrating why it is a sin to celebrate this day. It is also noted that Scripture never commands the celebration of this day and that there is no evidence that Christ and the Apostles ever celebrated this day--in fact, this syncretism of paganism and "Babylonian" Christianity was not first celebrated until 354 A.D. (when December 25 was chosen, in accord with the Pagan feast of Saturnalia, as the day of "celebration").
Price also clearly shows that to call yourself Reformed while you hold on to this Roman Catholic/Pagan monument of idolatry makes for a serious contradiction in your testimony--as the best Reformed churches have always disciplined those (in accord with Scriptural teaching) who broke the second and fourth commandments by keeping antichristian festival days like Christ-mass, Easter, etc.
Citations from Luther, Calvin and the company of Geneva Pastors, the Church of Scotland's First Book of Discipline, the 1620 Dutch Synod, the Civil Government of Holland (1625), the British Colonies in the U.S. and the Westminster Assembly all speak with one voice against this Romish corruption. Common objections against the classic Reformed position are also answered.
"Thus saith the LORD, Learn not the way of the heathen" (Jer. 10:2).
For more information see Christmas: A Biblical Critique by Kevin Reed.