The NT advances certain principles that foster fairness, forgiveness, patience and unity. For instance: “And be kind to one another, tenderhearted, forgiving one another, just as God in Christ also forgave you” (Eph 4:32). We should be careful not to engage in evil suspicions (1 Tim 6:4). Further, love “bears all things, believes all things, hopes all things” (1 Cor 13:7). We ought to attribute to people the best motives and be optimistic about their growth and improvement. All these perspectives are good and right. However, if not judiciously exercised they might lead to trouble. How so?

First, they can create a vulnerable idealism. For example, if a false teacher enters a congregation cloaked behind friendliness, humor and generosity, we might fail to recognize him because of our good nature. He may present himself as open-minded and invite us to study a thorny issue – which happens to be his favorite hobby that he pushes everywhere he goes.

A similar pattern affects naïve, young people in a romantic context, often females. They get involved with a troubled young man who plays upon their sympathies to redeem him and make him a better person. What Christian doesn’t want to see someone saved and grow into a faithful disciple? Sadly, many unsuspecting young ladies have had their faith shipwrecked or entered into an unhappy marriage by “spiritual gullibility,” the lack of wariness and insight that sees the reality of a dangerous or unseemly situation. Here are some principles to balance the tendency toward naivety:

“Behold, I send you out as sheep in the midst of wolves. Therefore, be wise as serpents and harmless as doves” (Mt 10:16). “Wise as serpents” is a figurative image. A snake’s body structure places it at a disadvantage in escaping danger. It must rely on stealth, camouflage and passive defense as it lacks mobility and dexterity. Jesus tells his disciples that both civil and religious authorities will persecute them (10:17-18); even family and friends will turn on them (10:21-22). The weapons of our warfare are not carnal (2 Cor 10:4); we don’t “fight fire with fire” but are to be “harmless as doves.” We must be judicious, size up situations accurately and respond carefully.

But sometimes the wolf comes to us: “Beware of false prophets, who come to you in sheep’s clothing, but inwardly they are ravenous wolves. You will know them by their fruits …” (Mt 7:15ff). You won’t always recognize false teachers by their words, for they “flatter[ing] people to gain advantage” (Jude 16). They “secretly bring in destructive heresies” and “will exploit you with deceptive words” (2 Pet 2:1, 3). What characterizes false teachers? They are “obsessed with disputes and arguments over words, from which come envy, strife, reviling, evil suspicions, useless wranglings of men of corrupt minds and destitute of the truth …” (1 Tim 6:4-5). Has this person caused trouble in other congregations? Why does he want to talk about the same thing every time you are with him? Why is he so adamant about his position? Does he say he is open-minded but acts as if his mind is firmly made up?

“Beware lest anyone cheat you through philosophy and empty deceit, according to the tradition of men, according to the basic principles of the world, and not according to Christ … Let no one defraud you of your reward, taking delight in false humility and worship of angels, intruding in to those things which he has not seen, vainly puffed up by his fleshly mind, and not holding fast to the Head …” (Col 2:8, 18-19). False teachers are often fairly intelligent people. It takes creative scholarship and deft weaving together of passages to concoct elaborate doctrinal schemes that defy Scriptural truth. We must “beware” of attempts to cheat us and steal our reward. Paul warns the Colossians that those who pervert truth display false humility; in actuality, they are arrogant and cock-sure of things they do not understand.

“O foolish Galatians! Who has bewitched you … Are you so foolish? …They zealously court you, but for no good …” (Gal 3:1, 3, 4:17). The Galatians had gullibly allowed the defenders of Judaism to infiltrate their thinking. In spite of the fact that “Jesus Christ was clearly portrayed among [them] as crucified” (3:1b), they had become “estranged from Christ” (5:4) by accepting a doctrine that said in effect Christ’s sacrifice was insufficient. Modern cult members fall prey to this kind of thinking when Mormons, Jehovah’s Witnesses, et. al. teach that something outside of the new testament is needed for “complete insight.” Paul’s confrontational language shows that the Galatians initially had a proper understanding of the truth but had allowed themselves to be snookered.

“For the sons of this world are more shrewd in their generation than the sons of light” (Lk 16:8). While we do not use the world’s tactics, we might take some commonsense lessons from the world. “Jesus is not telling us that we should become worldly-minded or crooked. He is stating the obvious fact that in worldly matters worldly people often show more astuteness or shrewdness than God’s children do in matters affecting their everlasting salvation” (Hendriksen, Commentary on Luke 770).

Humility does not equal gullibility. Trust does not cancel caution. Kindness does not mean leaving oneself (or family, or congregation) vulnerable to an unscrupulous, soul-destroying false teacher. Hoping for a positive outcome does not mean yielding to evil men. True love is not excusing the faults of a boy/girlfriend and sacrificing one’s soul to save a self-centered user. We must understand what is at stake and love the fox while not letting him in the henhouse.