Cults grow, in large part, because of the vacuum left by the absence of solid biblical teaching within evangelical churches themselves. One of the most common techniques, known as “fishing in the aquarium,” consists of internal proselytizing aimed specifically at poorly discipled Christians. To do this, the group uses familiar language and appearance, lowering suspicion and easing a gradual approach.
Exclusivism progressively isolates the member, convincing him that only that group holds the complete truth. Blind submission replaces the final authority of Scripture with the absolute authority of a human leader, who in practice comes to determine what is right or wrong for all followers. Selective use of the Bible, meanwhile, is perhaps the subtlest technique of all. The sacred text is not used to search for truth, but to confirm what the group has already decided to believe.
A cult does not need to convince someone of everything at once. It only needs to convince them of something seemingly small. From there, the rest tends to follow gradually, in a process almost imperceptible to the one being led. Paul warned the elders of Ephesus to pay careful attention to themselves and to the whole flock in which the Holy Spirit had made them overseers, to shepherd the church of God (Acts 20:28). That pastoral vigilance remains one of the best safeguards against this kind of internal proselytizing.
There is also a specific category of secret societies, such as Freemasonry, the Rosicrucians, and Scientology, which share certain characteristics — among them occultism, secretive structure, and a certain spiritual elitism — despite significant differences in their outward appearance and claims. Freemasonry, despite the fraternal language it employs, presents itself as a religious system marked by oaths that, in practice, demand a choice between the Lodge and Christ. The member who fully accepts Masonic teaching ends up, logically, denying central aspects of the historic Christian faith. The Rosicrucians deny the sufficiency of Scripture and reduce Jesus to the status of a cosmic master among other spiritual avatars considered equally valid. Scientology, in turn, replaces the biblical concept of sin with the idea of “mental error,” and the grace of God with purely human techniques and merit.
Where secrecy becomes a condition of belonging to a religious group, biblical discernment must be exercised with even greater care. One must honestly ask what exactly is being hidden, and from whom that information is being kept. Jesus taught the opposite: “what I tell you in the dark, say in the light, and what you hear whispered, proclaim on the housetops” (Matt 10:27). This principle of transparency stands in direct contrast to the logic of treating secrecy as a spiritual value.
Evaluate your own church: is discipleship solid enough to protect a newly converted Christian from the internal proselytizing practiced by cultic groups? Write down the four recruitment techniques mentioned here and give a real or hypothetical example of each. Also memorize 1 Timothy 2:5: “there is one God, and there is one mediator between God and men, the man Christ Jesus,” as a short, clear answer to any system that offers another spiritual mediator in his place.
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