Found in North America, the venomous coral snake is known for its deep red, yellow and black-colored banding. These snakes average three feet in length and are not usually aggressive. Though only 1% of snake bites each year in America are from coral snakes, they possess potent venom. Their bites are extremely painful and if left untreated can cause cardiac arrest. Interestingly, the harmless milk snake shows a striking resemblance to the coral snake. The similarity, known as mimicry, acts as a defense scaring away potential predators. This striking resemblance has led to a saying, or mnemonic, used to distinguish between the deadly coral snake and harmless milk snake. Boy scouts will tell you it goes like this: “Red on black: a friend of Jack; red on yellow: you’re a dead fellow.”
Distinguishing the harmless from the harmful is a spiritual discipline also. In the New Testament Jesus warns His followers to beware of false prophets who come to them in sheep’s clothing, but inwardly are ravenous wolves (Matt. 7:15). Jesus wants His disciples to be alert to the deadly fact that there are spiritual impersonators out in the world who say they are apostles but who are not, and if entertained will preach another Jesus and a different gospel to great harm (Rev. 2:2; 2 Cor. 11:2-4). Paul speaks similarly in his farewell speech to the elders at Ephesus, “Therefore take heed to yourselves and to all the flock . . . For know this, that after my departure savage wolves will come in among you, not sparing the flock” (Acts 20:28-29). Elsewhere, Peter, John, and Jude also warn of the danger of theological insurgents embedding themselves in the church with deceptive and damaging effect (2 Peter 2:1-3; 1 John 4:1-3; Jude 3-4).
Consequently, Christians must take error seriously and develop a discerning eye for that which does not square with the biblical gospel as taught by Christ and His Apostles. Just as there are doctrines that are true and if believed upon bring about salvation, so there are doctrines that are false and if believed upon bring about damnation (Gal. 1:6-9). There are doctrines of demons that land people in hell (1 Tim. 4:1)! To help us be discerning Jesus taught that you can spot the false teacher by their bad fruit (Matt. 7:16-20). Just as a bad tree bears bad fruit so the false prophet will manifest, in words and actions, that which is unhealthy and unholy.
In terms of bad fruit, you and I need to do some math in relation to false teachers and teaching. False teachers are always marked by addition, subtraction, multiplication, and division in relation to the gospel. One, false teachers invariably add to God’s word through tradition, new revelation, or other writings. Two, false teachers always subtract from the fullness of Christ’s person and the finality of His sacrificial work by either denying His deity or supplementing the Cross. Three, false teachers manifestly multiply the requirements for salvation by requiring faith and works, grace and law, mercy and merit. Four, false teachers deliberately divide the body of Christ by drawing disciples after themselves.
When it comes to false teachers do the math!