The Bible certainly teaches both separation from the world (“personal separation,” for example, 1 Jn. 2:15-17) and from false teachers (“ecclesiastical separation,” 2 Jn.), but not as these classifications are often understood by fundamentalists.
For one thing, the Bible requires we avoid sin, but not humanly devised taboos. Only God gets to define sin.
So, separation from the world isn’t identical to avoiding alcohol and Columbian cigars and movie theaters and Texas hold ’em and Lamborghini convertibles. At least, the Bible doesn’t say so, and the Bible alone is our standard. It’s more than ironic that some of the same people who rail against (for example) alcohol are quite tolerant of fornication. This is Phariseeism with a vengeance (Mk. 7)
On the matter of ecclesiastical separation, we need to recall that the Bible warns again and again of false teaching (in almost every book of the Bible except perhaps Ruth and Philemon), but it’s interesting that in all of Paul’s (and John’s, Rev. 2-3) letters to the erring churches, not once did he exhort the faithful to leave the church, even when the church was in danger of losing the Gospel, as in Galatians. Rather, he exhorted the godly to expel the unrepentant. His form of separation seemed to be formal exclusion: what we term excommunication. Of course, he warned about unequal yokes with unbelievers (2 Cor. 6:14f.), but he’s talking about Christians frequenting pagan temples, not the church of Jesus Christ. A church can apostatize and lose the light of the Lord’s presence (John warns the churches of Revelation), but God’s the one who removes the light, not man.
I appreciate the zeal of many separatist fundamentalists for the truth, but their separatism needs to be governed by the Bible, not by personal whims and “standards” and their celebrity preachers.
I hope this helps.
Much respect, in Him,
Dr. P. Andrew Sandlin