There has been a lot of talk about heresy thrown around on the Internet lately.
The frequency and volume of the accusations suggest that some Christians may have lost a sense of the gravity of the charge of heresy. The time has come to call for a strong dose of humility, restraint, and a clear and informed definition of orthodoxy and heresy.
DON’T WATER DOWN THE WORD
What is needed is a clear definition of heresy that is capable of distinguishing between those Christians who hold doctrines we disagree with from those who deny central truths of the Christian faith. Such a definition will require wisdom and discernment in how to engage those whose beliefs or teachings are not helpful, but it will avoid a dangerous overuse of the heresy charge, which waters it down and strips it of its usefulness.
RIGHT DOCTRINE IS IMPORTANT
We care deeply about right doctrine because the Bible does. The Bible has strong language to use against false teachers who promote doctrines that undermine the gospel. As Bruce Demarest notes:
The New Testament expresses serious concern for “false doctrines” (1 Tim. 1:3; 6:3) and places the highest priority on maintaining “the pattern of sound teaching” (2 Tim. 1:13; cf. 1 Tim. 6:3). Scripture urges Christians to be alert to doctrinal deception (Mt. 24:4) and to avoid heresy by carefully guarding the pure content of the gospel (1 Cor. 11:2; Gal. 1:8). 
In Galatians 1:9, Paul uses the strongest words possible against those who distort the gospel, writing, “If anyone is preaching to you a gospel contrary to the one you received, let him be accursed.” And the Apostle Peter warns against “false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction” (2 Pet. 2:1).
HERESY IS A WEIGHTY CHARGE
As is clear from the New Testament, the apostles were not afraid to call out heresy when they saw it. If a teaching or practice threatened the integrity of the gospel, it was strongly condemned (as in the case of Peter and the circumcision party described in Galatians 2). However, the charge of heresy was a weighty one that was not made lightly, nor was it used whenever there was theological inaccuracy or imprecision (think of the response to Apollos in Acts 18:24–28).
In contrast to the easy accusations of heresy lobbed around the Internet today, historically both the Roman Catholic and Reformed traditions have been careful to specify different degrees of heretical or unhelpful teaching. In Catholicism, a blunt denial of an explicitly defined Church doctrine is heresy in the first degree. A doctrine that has not been explicitly defined by one of the Church’s articles of faith but diverges from the received majority view is considered an opinion approaching heresy (sententia haeresi proxima). One who holds a position that does not directly contradict received dogma but logically entails denial of an explicitly defined truth is said to be erroneous in theology (propositio theologice erronea). Finally, a belief that cannot be definitively shown to be in opposition to an article of faith of the Church is said to be suspected or savoring of heresy (sententia de haeresi suspecta, haeresim sapiens).
NOT ALL THEOLOGICAL ERRORS ARE EQUALLY SERIOUS
Similarly, the Reformed tradition historically distinguished three kinds of doctrinal error related to fundamental articles of the faith: 1) errors directly against a fundamental article (contra fundamentum); 2) errors around a fundamental or in indirect contradiction to it (circa fundamentum); 3) errors beyond a fundamental article (praeter fundamentum). Richard Muller explains them like this:
The first kind of error is a direct attack—such as those launched by the Socinians—against the divinity of Christ or the Trinity. The second is not a direct negation or an antithesis but rather an indirect or secondary error ultimately subversive of a fundamental—such as a belief in God that refuses to acknowledge his providence. The third category of error does not address fundamental articles directly or indirectly but rather involves faith in problematic and curious questions (quaestiones problematicas et curiosas) that do not arise out of the revealed Word—hay and stubble!—and that, because of their curiosity and vanity, constitute diversions from and impediments to salvation.
The point is that historically both the Roman Catholic tradition and the Reformed tradition have understood that not all theological errors are equally serious. Theological historian David Christie-Murray distinguishes between orthodoxy, the body of Christian belief which has emerged as a consensus through time as the church reflects on Scripture; heterodoxy, Christian belief which differs from orthodoxy; and heresy, belief that diverges from orthodoxy beyond a certain (ill-defined) point. We may agree that there exists a perfect orthodoxy in the mind of God, but the proliferation of schisms, disagreements, and divisions throughout church history points to the fact that we as fallible humans are imperfect at agreeing precisely on that orthodoxy. Consequently, we must fall back on a humble definition of orthodoxy by drawing on the consensus of our interpretation of Scripture, church history, and reason.
WE’RE NOT SAVED BY OUR INTELLECTUAL PRECISION
Because the line between heterodoxy and heresy is blurry, we need lots of wisdom, discernment, and humility before we declare that someone has departed into full-blown heresy. In addition, we must remember that the entirety of what we think Christians should believe is not identical to what a person must believe to be saved. We believe in justification by faith in Christ, not justification by accuracy of doctrine. We are saved by the grace of Jesus, not our intellectual precision.
HOW THE EARLY CHURCH DEALT WITH HERESY
Core Christian doctrines such as the Trinity, the nature of Christ, and the canon of Scripture were developed through the early church’s struggles with heresy. When teachers arose and began to lead movements with teachings blatantly opposed to the apostolic tradition, the church was drawn by necessity to clarify and articulate the essential elements of the apostolic teaching. The early church creeds were formulated to meet this need for clear definition of the essentials.
The earliest creeds of all are arguably to be found in Scripture itself. Many scholars believe that Paul recites an early creed in his letter to the Corinthians when he summarizes the facts that he taught as “of first importance”: “that Christ died for our sins in accordance with the Scriptures, that he was buried, that he was raised on the third day in accordance with the Scriptures, and that he appeared [to the apostles and many others]” (1 Cor. 15:3–7).
SOME BASICS OF FAITH
After the apostolic age, the early church possessed what was known as “the rule of faith,” which Demarest describes as “brief summaries of essential Christian truths.” In the second century, Irenaeus described the rule of faith in this way:
One God, the Creator of heaven and earth, and all things therein, by means of Christ Jesus, the Son of God; who, because of His surpassing love towards His creation, condescended to be born of the virgin, He Himself uniting man through Himself to God, and having suffered under Pontius Pilate, and rising again, and having been received up in splendor, shall come in glory, the Savior of those who are saved, and the Judge of those who are judged, and sending into eternal fire those who transform the truth, and despise His Father and His advent.
As the early Christian community dealt with new heretical movements, the rule of faith gave birth to more precise statements of the essentials of the faith, such as the Apostles’ Creed and the Nicene Creed. These widely accepted formulations of the essential “right doctrine” (orthodoxy) handed down from the apostles were crucial for combating heresy. Importantly, the early church did not consider every potential wrong belief heretical. Only those teachings that contradicted the essential elements of the faith were to be labeled heresy.
RELEARNING HOW TO TEST HERESY
The current climate shows that we need to relearn the ability to care about right doctrine and have earnest doctrinal disagreements without proclaiming “Heresy!” over every point at which we disagree. We need a more restrained definition of heresy drawing on the early church creeds. The Nicene Creed is a historic, globally accepted ecumenical creed that encapsulates the good news of the gospel into a short and rich summary. It covers the basic essentials of 1) who God is, 2) what God is like, and 3) how God saves.
If a believer authentically holds to the Nicene Creed, we should not call them a heretic, no matter how strongly we believe they are gravely in error on the details or on other doctrines. A good shorthand for heresy, then, is to ask, “Can they say the Nicene Creed and mean it without their fingers crossed?” If the answer is yes, they may still be wrong, and they may be heterodox, but we cannot call them heretics, because they fit within the bounds of historic Christianity.
WHERE DO WE GO FROM HERE?
Even with this narrow and confined definition of heresy, we can still discuss and debate with those whose beliefs are unhelpful. We can still say that their teachings are not a good application of Scripture to life and doctrine. But we treat them not as heretics, but as brothers and sisters with whom we lovingly disagree. As the famous saying goes, “In essentials unity, in non-essentials liberty, and in all things love.”
Such an attitude of humble, charitable engagement stands in stark contrast to the spirit of the blogosphere today. Rather than being fundamentalists who turn disagreement into division, we should contend for the truth with humility and grace. That’s how Jesus treated us.
———————- Bruce Demarest, “Heresy,” New Dictionary of Theology (Downers Grove, IL: IVP Academic, 1988), 293.  J. Wilhelm, “Heresy,” in The Catholic Encyclopedia (New York: Robert Appleton Company), http://www.newadvent.org/cathen/07256b.htm.