Chris Coleman has a couple of brief passages from Ursinus on this essential distinction.The failure to make this distinction either by ignoring it altogether or by confusing circumstances and elements has resulted in great mischief in Reformed congregations.

Another thing with which I’ve been impressed in recent years and which one notices in Ursinus’ definitions, is how narrowly “circumstances” is to be defined. It is not to be used to smuggle into worship the stuff that we want to do (will worship).

Ursinus gives this list of examples: 

of which kind are the time, the place, the form and order of sermons, prayers, reading in the church, fasts, the manner of proceeding in the election of ministers, in collecting and distributing alms, and things of a similar nature

None of the things Ursinus listed are actually religious in nature. In their nature circumstances do not involve our approach to God or our response to his Word. Those things are elements (word, sacrament, prayer). Circumstances are the times and places at which, and the languages with which we worship, but the way we respond to or approach God are regulated strictly by God’s Word. This is how the Reformed understood the function of the formal principle of the Reformation (sola Scripture) in worship.

In the middle of the 17th century John Owen said essentially the same thing:

Whatever is of circumstance in the manner of its performance, not capable of especial determination, as emerging or arising only occasionally, upon the doing of that which is appointed at this or that time, in this or that place, and the like, is left unto the rule of moral prudence, in whose observation their order doth consist. But the superaddition of ceremonies necessarily belonging neither to the institutions of worship nor unto those circumstances whose disposal falls under the rule of moral prudence, neither doth nor can add any thing unto the due order of gospel worship; so that they are altogether needless and useless in the worship of God.

An element is not morally indifferent. An element is morally and religiously obligated upon the Christian by God. A circumstance is morally indifferent. It may be done or omitted. As Bishop John Hooper argued in the 16th century, a circumstance neither adds anything to worship by its use or removes anything by it’s omission. Judging by some of the responses (private and public) to my criticisms of instruments it’s evident to me that many who defend uninspired songs and musical instruments as mere circumstances don’t really regard them as circumstances. As I keep saying, if I proposed moving the the 11AM service to 10AM, I doubt that people would be so passionate and even heated.

Praying at 10AM or 11AM neither adds anything to worship nor takes anything away. We can’t say the same thing about the use of uninspired songs and musical instruments. We can’t say the same thing about re-instating ceremonies or aspects of the Mosaic cultus (worship). Christian worship is semi-eschatological. It is the worship of those who have been united to Christ, the fulfillment of all the types and shadows. Why then would we want to re-introduce aspects of ceremonial, typological worship (e.g. musical instruments or animal sacrifices) into the worship of those who have been freed from the typologies?

Another way to sort out this question is to ask what “circumstances” and “elements” meant to those who gave us this distinction. Calvin, Ursinus, Ames, and Owen did not use uninspired songs and musical instruments in worship. When our catechisms and confessions were composed and adopted the intent was that Reformed congregations should sing God’s Word without instruments.

When instruments were first re-introduced into Reformed worship, after the Reformation, they were not re-introduced as circumstances but rather for pragmatic reasons. The defense of musical instruments and uninspired songs as “circumstances” was created after the fact (ex post facto) in order to rationalize our departure from the historic and confessional understanding of the second commandment.