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. Do men gather grapes from thorn bushes or figs from thistles? Even so every good tree bears good fruit, but a bad tree bears bad fruit. (Matthew 7:15–20—NKJV)

The Sermon on the Mount is usually remembered for its beautiful words, its focus on service, uplifting of the downtrodden, and its prescription for the godly qualities of the people who will populate the Millennial Kingdom. Take note that sprinkled between “uplifting” passages such as the Beatitudes, the Golden Rule, the “Lord’s Prayer,” “Ask, Seek, and Knock” praying, and the Parable of “The Wise and Foolish Home Builders” there are the “admonishing” passages concerning “The Straight and Narrow Way,” the meaning of adultery and the Jewish law concerning divorce, Christ’s insights on the letter and spirit of the Old Testament laws, treasure storing, and a hefty section on judgment which includes a discussion concerning false prophets.

God is not fooled by a false prophet and He does not want His people to be fooled by them either. The section of the Sermon on the Mount found in Matthew 7:15–20 deals with this very critical need for all believers. What our Lord unfolds for us is the right way to judge hidden things! A false prophet does not wear a sign that declares his status. Instead, he masquerades as one of God’s faithful while sounding forth a message that he claims comes from God. What is a believer to do? How can a believer preserve himself from the snares set by any false prophet? How can you judge the hidden things?

First, accept The Challenge found in verse 15. Beware (literally—“hold your mind away from”) false prophets. Christ’s command is to be discerning, or judging, if you will. The reason sheep need a shepherd, and a church needs a pastor, is that false prophets are described by our Lord as wolves in sheep’s clothing. The word picture is of a long garment made of wool (talith—worn to symbolize the appearance of a righteous man as in Mark 12:38 or Hebrews 11:37). He is a wolf clad in sheep hide, or skin. The inner nature of a wolf is described as ravenous, greedy, violent, covetous, deceptive, exploitive, and dangerous to the helpless and unsuspecting sheep. The sheep’s best defensive strategies are to be vigilant and to run—the greater the head start the better! If a voracious wolf is able to sneak in among the sheep, cloaked in humble simplicity and gentleness, what chance does a sheep have to escape injury? The challenge for the “sheep” is to detect every hidden wolfish intention and nature disguised as God-fearing morality and demure harmlessness.

Second, take a lesson from Common Sense found in verse 16. Even natural man can distinguish between fruits. You do not go to gather grapes from a thorn bush or figs from a prickly thistle. Fortunately, there is an inseparable correlation between the nature of the plant and the fruit produced. Every man goes through life producing fruit, just as a living plant does. The nature of the man determines the type and quality of each fruit. Do not be afraid to be a spiritual fruit inspector just as you must be in a farmer’s market. A believer ought to practice spiritual discernment by exercising discriminating choice between bad, good, better, and best. A false prophet is one who claims to speak for God but, in his word or deed, diminishes the incomparable majesty of God or downplays the superlative sacrifice of Christ, thus showing his true nature. In playing to the vanities, the applause, or the sensibilities of his audience, he is producing rotten fruit that is the result of his unregenerate nature.

Third and fourth, observe what Every Man Can Only Do found in verse 17 and what Every Man Cannot Do in verse 18. Men can only produce fruit that is generated by their inner nature and they cannot produce fruit that is not descended from their nature. The good (intrinsically good—agathon) tree will produce good (beautiful—kalous) fruit, the bad tree will produce rotten fruit. No matter how “beautiful” the appearance of the claims of the false prophet may be, his claims are absolutely no guarantee of the soundness of the inner nature. Fruit will come as the visible outgrowth of the inner nature and that fruit must be the judgment point.

Fifth, remember that this discerning act is really God’s Judgment Call, not yours (verse 19). Those who do not faithfully preach and teach only Christ will be cut off, discarded, and cast into the fire. This is God’s verdict.

Sixth, the Practical Conclusion for every believer is to humbly and obediently remain vigilant by careful examination of a man’s spiritual fruit to determine whether that man is a false prophet or an authentic servant of the Most High (verse 20). “By their fruits you will [fully] know them.” Do not be afraid to rightly judge hidden things (John 7:24). Trust and obey.