Richard Barcellos directed me to a new booklet on the three-fold division of the law. He notes:
It is quite common in our day to deny the three-fold division of the law – moral, ceremonial, judicial. No one who has read up on the issue denies that Reformed theology teaches this division. It is in Calvin and other 16th-century theologians, in the 17th-century men, and in Reformed confessions and catechisms. The historical-theological question concerning the Reformed tradition on this issue is not disputed. What is disputed, however, is whether or not the division pre-dates the Reformation and, more importantly, whether the Bible itself makes such distinctions. I think the answer to both questions is yes and so does Jonathan F. Bayes in this excellent piece on the three-fold division. It is a very well-written and relatively easy-to-read piece. I recommend it very highly!
I think the end of Bayes’ piece provides some interesting challenges to those who deny any distinction within the law.