There are some Christians who speak of primary and secondary separation. By primary separation they mean separation from those who teach false doctrine. To them secondary separation involves separation from those believers who do not practice primary separation. Many Christians have ridiculed the position of secondary separation as unscriptural. As shown above, however, faithfulness to biblical principles sometimes makes separation from other believers necessary. This kind of separation should not be called "secondary" but biblical separation.
True biblical separation is a matter of love: a love for God that rejects the world system, a love for the church that will not tolerate false teachers who desire to lead the sheep astray and to devour them, and a love for the Christian brother–a love that is willing to endure even a break in fellowship in order to provoke him to do right. In his practice of separation the Christian should not become frustrated, vindictive, or mean. He should not be hasty to condemn others on the basis of unproven rumors. He should demonstrate a godly patience because he knows that God will eventually judge all ungodliness (Jude 14-15), whether it be the ungodliness of the world, of the false teacher, or of a disobedient brother.
A Christian whose sin is not publicly known and who is not leading others astray by his example should be rebuked privately and in the spirit of the New Testament. While a stronger brother should try to rebuke and, if possible, restore a weaker brother, he should do it in a spirit of meekness, remembering that he may also be tempted. However, public sin committed by a public figure must be publicly rebuked for the sake of those who are being deceived. For example, a man who advocates fellowship with apostasy and who cooperates with cultists, heretics, false teachers, unbelievers, and Romanists is guilty of a public defiance of God's command. For the sake of those whom he is leading astray or who might be led astray by him if not properly warned from the Scripture, a faithful minister of Christ must hold that man up as an example of a false teacher even though he pretends to, and perhaps to an extent does, preach the gospel. He is not, however, abiding in the doctrine of Christ and so must be exposed as a wolf in sheep's clothing. It is unfortunate that men are associated with positions. It would be well if we could concentrate only on the position and deal with the issue of scriptural disobedience or compromise; but when some man is the prime instigator, promoter, and advocate of an unbiblical position, that man must be exposed as a false teacher as we denounce the sin he is promoting.
Many who argue against scriptural separation as presented here are not against separation as a principle. They will separate from other believers because of disagreements over minor matters of interpretation or practice which do not involve the fundamentals of the Faith. But they have an unbalanced view of the Scripture and fail to see the seriousness of the sin that makes separation absolutely necessary. The believer who immerses himself in the Word of God and seeks to mature spiritually must learn to view sin the way God does.