—Deuteronomy 22:9-11 (NASB)
We have either experienced personally or know first-hand of someone who has begun the journey on the road to a personal relationship with Christ only to end up somewhere else, far off-course from that originally intended. Sometimes it's obvious that a conscience choice was made at some point to simply leave the path—what the Bible often refers to as "turning to the right or the left"—other times it's not so obvious, seeming to have occurred by going off-course by tiny increments so as not to abruptly notice that the path has eventually been left. This is an especially delicate discussion in trying to determine why a person, ministry, or even entire spiritual movement appears to have begun legitimately and derived its source from God, but later mutates into something else, something eventually and obviously no longer of God. What went wrong? How can we avoid making such mistakes ourselves?
A common scenario is that it starts out pure, but along the way begins to allow something else to be added to it, something NOT pure. As it continues to increasingly mix the impure with the pure, it all eventually stinks. This is not just true of earthly, physical things, but even more so of the spiritual. The definition of "heresy" is to take truth and lay it alongside error. There may be some truth, but once it's mixed with error the whole result is deadly wrong. Or as Jesus stated in Matthew 6:25, "No one can serve two masters; for either he will hate the one and love the other, or he will be devoted to one and despise the other."
The essence of a successful spiritual relationship is sanctification, the pursuit of being wholly and exclusively devoted to Christ and absolutely no other. We don't sow any other doctrine but His alone. We don't build working relationships with any but our fellow workers for His kingdom. We are clearly identified as those whose clothes have been washed and cleansed in His blood, not sharing in the corruption and decay of this present world. The path whose course veers an inch at a time from the main road begins with small, minute allowances of earthly elements to be mixed with the heavenly until it leads to and becomes something else entirely.
We're not entirely blind to this process. The fact that we're struggling with an area is the notice the Spirit is giving us that we're allowing error to become an equal partner with truth. We're allowing earthly philosophies to mix with sound biblical doctrine, allowing ourselves to be unequally yoked with unbelievers, attempting to mix the treasures of heaven with the material desires of earth, or any combination thereof. We struggle because we're allowing an unhealthy mixing to occur. The question that presents itself is what we're going to do to no longer tolerate the mixture.
—Colossians 1:21-23 (NASB)