In an article in The Presbyterian Guardian, J. Gresham Machen wrote on the problems of terms commonly used to describe the historic Christian faith. Here are a few excerpts:
Many years ago, …some brilliant person said: “Orthodoxy means ‘my doxy’ and heterodoxy means ‘the other man’s doxy’.”
The unknown author of that famous definition–unknown to me at least–may have thought that he was being very learned. Knowing that the Greek word “heteros,” which forms a part of the English word “heterodoxy,” means “other,” he built his famous definition around that one word, and “heterodoxy” became to him “the other man’s doxy.”
Possibly, however, he knew perfectly well that he was not being learned, and merely desired to have his little joke. As a matter of fact, the Greek word “heteros” in “heterodoxy” does not just mean “other” in the ordinary sense of that word, as when we speak of “one” man and “another” man, but it usually means “other” with an added idea of “different.”
…Accordingly, the real state of the case is that “orthodoxy” means “straight doxy” and “heterodoxy” means “something different from straight doxy”; or, in other words, it means “crooked doxy.”
…What term shall we who stand for the Bible in the Presbyterian Church in the U.S.A. use to designate our position? For my part, I cannot say that I like the term “Fundamentalism.” I am not inclined, indeed, to quibble about these important matters. If an inquirer asks me whether I am a Fundamentalist or a Modernist, I do not say, “Neither.” Instead, I say: “Well, you are using terminology that I do not like, but if I may for the moment use your terminology, in order that you may get plainly what I mean, I just want to say… that I am a Fundamentalist from the word go!”
However, it is a different matter when we are choosing terminology that we shall actually use about ourselves. When we are doing that, I think we ought to be just as careful as we possibly can be.
The term “Fundamentalism” seems to represent the Christian religion as though it had suddenly become an “ism” and needed to be called by some strange new name. I cannot see why that should be done. The term seems to me to be particularly inadequate as applied to us conservative Presbyterians. We have a great heritage. We are standing in what we hold to be the great central current of the Church’s life–the great tradition that comes down through Augustine and Calvin to the Westminster Confession of Faith. That we hold to be the straight high road of truth as opposed to vagaries on one side or on the other. Why then should we be so prone to adopt some strange new term?
Well, then, if we do not altogether like the term “Fundamentalism”–close though our fellowship is with those who do like that term–what term shall we actually choose?
“Conservative” does seem to be rather too cold. It is apt to create the impression that we are holding desperately to something that is old just because it is old, and that we are not eager for new and glorious manifestations of the Spirit of God.
“Evangelical,” on the other hand, although it is a fine term, does not quite seem to designate clearly enough the position of those who hold specifically to the system of doctrine taught in the Westminster Confession of Faith, as distinguished from other systems which are near enough to the truth in order that they may be called “evangelical” but which yet fall short of being the system that is contained in God’s Word.
Therefore, in view of the objections that face the use of other terminology, I think we might do far worse than revive the good old word “orthodoxy” as a designation of our position.
“Orthodoxy” means, as we have seen, “straight doxy.” Well, how do we tell whether a thing is straight or not? The answer is plain. By comparing it with a rule or plumb-line. Our rule or plumb-line is the Bible. A thing is “orthodox” if it is in accordance with the Bible. I think we might well revive the word.
The Presbyterian Guardian, Nov. 4, 1935, “The Changing Scene and the Unchanging Word.”
The Machen Seminar 