Heresies are a bad thing. Any orthodox person knows that. But I see some value in them. Orthodoxy is defined, at its root, as "right belief". Heresy is defined as "at variance with orthodoxy". Thomas Aquinas defined heresy as "a species of infidelity in men who, having professed the faith of Christ, corrupt its dogmas." In other words, it takes a profession of faith to qualify as a heretic. It also takes a "right belief".
Heresies cause all sorts of problems. They cause division and schisms. They lead people from the truth. They lie and deceive and obscure right belief. There are all sorts of problems with heresies. But I still see value in them.
The first value I see is the division they provide. Yes, "provide." John wrote:
Children, it is the last hour, and as you have heard that antichrist is coming, so now many antichrists have come. Therefore we know that it is the last hour. They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us (1 John 2:18-19).
What does John mean, "They went out from us"? Most heretics I know about remained or still remain in churches. In what sense do they go out from us? I think it's plainly in their deviation from the truth. There is a body of truth in the Christian faith that is "right belief". When they deviated from that truth, they "went out from us." Why? "If they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us." So, to me, heresies are valuable because they point out who is "not of us" -- who the real anti-christs are. They illustrate the tares among the wheat. These people simply open their mouths and prove that they are against Christ by deviating from the Truth. I think that's helpful.
The other value is much greater. Heresies have provided, through the centuries, clarification of truth. Like a fire that burns off dross, heresiarchs have appeared on the scene creating firestorms of controversy. The Church gathers and addresses the question and the truth is outed. This pattern started at the beginning of Christianity, way back in the New Testament. Paul wrote 1Corinthians to a church that was practicing antinomianism -- no rules. They quarreled over who they followed (1 Corinthians 1:10-17). They had a man living in sin with his step-mother (1 Corinthians 5). They were getting drunk at the Lord's Supper (1 Corinthians 11:20-34). They were practicing mayhem with the spiritual gifts (1 Corinthians 12-14). Paul took them to task for ... these errors. The letter to the churches of Galatia was written to address the heresy of legalism, the belief that we can be saved and/or sanctified by being good. So Paul writes, "O foolish Galatians! Who has bewitched you? It was before your eyes that Jesus Christ was publicly portrayed as crucified. Let me ask you only this: Did you receive the Spirit by works of the law or by hearing with faith? Are you so foolish? Having begun by the Spirit, are you now being perfected by the flesh?" (Galatians 3:1-3). Sharp words for a sharp heresy. Paul's letter to the church at Colossae was written to address the heresy of gnosticism, a heresy that has raised its head again today. Gnosticism preached that if you were spiritual you could receive special knowledge, a secret knowing. One achieved this, they said, by self-deprivation. Paul said, "If with Christ you died to the elemental spirits of the world, why, as if you were still alive in the world, do you submit to regulations -- 'Do not handle, Do not taste, Do not touch' (referring to things that all perish as they are used)--according to human precepts and teachings? These have indeed an appearance of wisdom in promoting self-made religion and asceticism and severity to the body, but they are of no value in stopping the indulgence of the flesh" (Colossians 2:20-23). Instead of allowing for some "elemental spirits" who would provide special knowledge, Paul writes, "See to it that no one takes you captive by philosophy and empty deceit, according to human tradition, according to the elemental spirits of the world, and not according to Christ. For in Him the whole fullness of deity dwells bodily, and you have been filled in Him, who is the head of all rule and authority" (Colossians 2:8-10). Other books, such as Hebrews and 1John, were written to counter early error in the Church.
This pattern continued in the Church after the writing of the New Testament. Irenaeus's Contra Heresies was written to counter heresies of his day and served to crystallize much Christian doctrine. The Council of Nicaea met to counter the heresy of Arianism which denied the deity of Christ. Any position that denies the deity of Christ, then, has been clarified as heresy, outside orthodoxy, "out from us". The First Council of Constantinople addressed the Macedonius heresy which denied the deity of the Holy Spirit. The Council of Ephesus addressed the Nestorian and Pelagian heresies. The Nestorian heresy co-mingled the divine and human nature of Christ, and the Pelagian heresy denied the innate sinfulness of Man. Any position that mingles the humanity of Christ with the deity of Christ, then, has been clarified as heresy, outside orthodoxy, "out from us", and those who argue that mankind is basically good are classified as heretics, outside orthodoxy, "out from us". The Council of Chalcedon met to counter the heresy of the Monophysites that held that Jesus was never human. Any position that denies the humanity of Christ, then, has been clarified as heresy, outside orthodoxy, "out from us".
Well, you get the idea. Heresies have caused problems since the beginning of Christianity, but there has been benefits. (Maybe that's why a sovereign God would allow them, eh?) Paul wrote, "There must be factions among you in order that those who are genuine among you may be recognized" (1 Corinthians 11:19). Heresies have been the catalyst for gathering after gathering of the Church to crystallize and affirm the Truth over against the false. Without these heresies, these clarifications would never have occurred, beginning with the New Testament writings. And without these clarifications of orthodoxy -- right belief -- we would have a difficult time recognizing the anti-christs among us, those who go out from us, because they never seem to leave. Maybe it can be said that, although heresies themselves are evil, it is good that they exist.