We’re certain that the teaching is wrong.
The teaching will affect other doctrines. For example, if we abandon the inerrancy of Scripture, that will eventually have a significant impact on other doctrines.
The teaching will do significant spiritual harm. For example, believing that people of other religions can be saved without consciously believing in Jesus destroys the motive for evangelism and missions.
The doctrine is a historical aberration. A doctrine’s validity does not finally depend on its historical pedigree. But if a doctrine is utterly historical novel, that should create a presumption against it.
The doctrine’s advocates seem to refuse to be subject to Scripture.
The doctrine’s advocates manifest the deeds of the flesh, not the Spirit. When teachers manifest arrogance, deception, unrighteous anger, slander, and falsehood, rather than humility, openness to correction, kindness, and truthfulness, it plainly shows that what they teach is not the wisdom that comes from above (James 3:17-18).
Find more great resources for church health from Mark Dever and 9Marks Ministries at www.9marks.org