The Bible teaches personal separation—the commitment of an individual believer to maintain a godly standard of behavior, separating from those who are living an ungodly lifestyle (1 Corinthians 5:11). The Bible also teaches ecclesiastical separation—the commitment of a church to maintain the purity of the gospel message, cutting ties with those who have compromised their doctrine (Revelation 2:14–15). Secondary separation takes things a step further: not only does one separate from an individual or group due to sin or heresy, but one also separates from anyone who does not likewise separate from those individuals or groups.
Secondary separation works like this:
a) Mr. False is a heretic, teaching a false gospel.
b) We refuse to associate with Mr. False (and rightly so).
c) Mr. True, who is a sound, biblical teacher, speaks at a conference where Mr. False is also speaking.
d) We now refuse to associate with Mr. True, because of his association with Mr. False.
Practicing secondary separation is difficult because it is hard to stop at the secondary level. Using the names in the above example, what about other people who do not separate from Mr. True? If associating with Mr. True is wrong because of his tacit approval of Mr. False, then it would seem that someone who associates with Mr. True is living in sin, and we should separate from him as well. So, if Mr. Right (who does not support Mr. False) does not separate from Mr. True, do we need to also separate from Mr. Right? Now we have three levels of separation, but it does not stop there. What if Mr. Proper continues to associate with Mr. Right? Do we now need to dissociate from Mr. Proper? And what about all the people who still associate with Mr. Proper? Do we need to dissociate from them, too? It goes on and on. It would never stop.
We saw this kind of thing with Billy Graham. He often worked with people in theologically liberal churches to facilitate his evangelistic campaigns. For this reason, some thought that Christians should practice secondary separation and separate from Billy Graham. Then some advocated separating from anyone who did not also separate from Billy Graham. Carried far enough, such standards would result in a very small group of “purists” who can hardly fellowship with anyone else.
C.S. Lewis is another figure who could be the center of discussions about secondary separation. Lewis was a believer, but he held some problematic doctrines and freely associated with Roman Catholics, considering them to be true believers. We can choose to “separate” from Lewis (by not reading his books), but if we also choose to dissociate ourselves from anyone who does read his books, then we would pretty much isolate ourselves, because almost everyone in American evangelicalism reads C.S. Lewis. It is probably more helpful to read, enjoy, and recommend the works of C.S. Lewis and, when necessary, point out where we disagree with him and the reasons why.
Another problem with putting secondary separation into practice is that people often falsely brand someone as a heretic when, in reality, the person is a true believer who simply holds a different position on a secondary issue. Furthermore, there is often dispute on which issues are secondary.
Rather than trying to come up with some hard-and-fast rule concerning secondary separation, each situation should be evaluated on its own merits. If Mr. True begins to actively teach what Mr. False does, or if he begins to actively promote Mr. False as a reliable teacher, then we might want to draw back from Mr. True. If, on the other hand, Mr. True finds Mr. False to be a congenial man but disagrees with him on some key doctrinal points, then we might not need to separate from Mr. True.