(I am not sure that I have placed this in the correct forum here at PuritanBoard. Feel free to move it to a more appropriate forum if this is not the correct one.) I present the following questions for the sincere and thoughtful consideration of Presbyterian members here—although it is open to those of other traditions as well—because I am looking for answers drawn and cited from recognized Presbyterian sources, be they scriptures, confessions, catechisms, general assemblies, synods, or otherwise books and articles by theologians who are Presbyterian or whose material is generally accepted by Presbyterians; and, come to think of it, perhaps in that preferential order. (The theological opinions of members here are also welcome, of course, but I am looking for sources and materials which I can cite in a research paper.) 1. What is heresy? That is, when is a belief regarded as not just unorthodox but actual heresy? For example, it is my understanding that there are many Presbyterians who accept and believe evolutionary creationism and an earth that is billions of years old, even though the Westminster Standards speak of creation out of nothing in the space of six days. Although they might be regarded by some as holding an unorthodox view, they are not considered heretics. I raised this question with both the senior and associate pastors at my church (which is Baptist and thus neither helpful or relevant for resolving this in a Presbyterian context) and, at the end of our discussion, we were agreed that the only beliefs subject to the charge of heresy are those which touch upon the nature and character of God, his word, or the gospel. As such, affirming evolutionary creationism and an earth that is billions of years old is plausibly unorthodox but not necessarily heretical; unless one also denies that Adam was a real figure in history, which would be heretical given his import to soteriology (federal headship and imago Dei, original sin and the nature of man, contrast with the "last Adam," etc.). And so the late Harold Brown: "In the early church, heresy did not refer to simply any doctrinal disagreement, but to something that seemed to undercut the very basis for Christian existence. Practically speaking, heresy involved the doctrine of God and the doctrine of Christ—later called special theology and Christology" (Heresies [Doubleday, 1984], p. 2). This is all well and good for an independent Baptist congregation, but I wish to explore this question in a Presbyterian context (for it is a Presbyterian with whom I am engaging these issues) so I am looking for answers from recognized Presbyterian sources that I can cite. As for the holy scriptures, I know that the apostle Paul considered it heresy to preach a different gospel contrary to apostolic preaching ("not that there really is another gospel"), such that those who did so ought to be cut off and condemned (anathema esto; Gal. 1:6-9). What else do the scriptures have to say regarding heresy? What about Presbyterian confessions and catechisms and so forth? 2. Are the terms heretic and Christian mutually exclusive? In other words, does it follow that to call someone a heretic is to call them a non-Christian? This question is admittedly a bit sticky. For example, the Protestant faith is heretical on the Roman Catholic view; and yet Protestants, perhaps most effectively by those of the Reformed faith, would argue that they enjoy union with Christ and are thus Christians, notwithstanding the opinion of Romanists. So there is one sense in which the terms heretic and Christian are not mutually exclusive. But I am inquiring after a Presbyterian context, so I am looking for an answer that is consistent with the five solas of the Protestant Reformation and the confessional standards of orthodox Presbyterian churches. For example, suppose a Reformed Baptist called a Presbyterian heretical over the issue of infant baptism, given that the 1689 London Baptist Confession of Faith (LBCF) militates against such a practice—even though the Westminster Confession of Faith (WCF) and catechisms affirm it. Has the Reformed Baptist misapplied the term, or did he use it rightly (thus rendering the Presbyterian a "Christian heretic")? What I mean to ask is this: Is there a definition of heretic that transcends competing confessional orthodoxies which all Reformed churches acknowledge? Surely the matter is not so muddled that all Christians are thus inevitably heretics (since every Christian body will violate the orthodoxy of another Christian body). It must be the case that the Reformed Baptist in our hypothetical scenario has misapplied the term, for even his own confession subordinates itself to holy scriptures, the only infallible rule of Christian faith and practice (LBCF chapter 1, articles 1, 2, 6, 9, and 10). As Philip Schaff notes in The Creeds of Christendom, "The value of creeds [and presumably confessions and catechisms] depends upon the measure of their agreement with the Scriptures. ... The Bible has, therefore, a divine and absolute [authority], the Confession only an ecclesiastical and relative authority." There must be a set of orthodox dogmas to which all Reformed churches are agreed as delineating heresy, such that all other contentions permit communion of these saints as Christian brothers. And it is my hope that there is some record of this in sources from, or recognized by, orthodox Presbyterian churches confessing the Westminster Standards. (For my purposes there is no need for an orthodoxy that will include the Roman Catholic and Eastern Orthodox churches, so that can be left to the side. Those of the Protestant Reformation need only apply, so to speak.) 3. Can a Presbyterian properly identify as confessional if he does not subscribe to every single item of the Westminster Standards? I believe that in order to hold a teaching office in the Presbyterian church one must subscribe to the entirety of the Westminster Standards; however, I am led to understand that such is not required of the laity. For example, if a member in good standing of a Presbyterian church subscribes to the Westminster Standards excepting one part (which is not related to the nature and character of God, his word, or the gospel), then can he properly identify as confessional? Or was I misled and the laity, in fact, must subscribe to the entirety of the Westminster Standards in order to identify as confessional? I appreciate your careful and thoughtful contributions to answering these questions. Please remember to cite the references that your answers draw from, if any, so that I may examine them for myself and include them in my research.