What does it mean that you will know them by their fruit in Matthew 7:16?

But the believer may discern them by their fruits. They bear the character of thorns and thistles, harmful rather then productive, not ministering food for the need of souls. No child of God should be deceived by them. They tickle men's ears, usually appealing to the pride of intellect, but ignorant of the truth that reaches consciences and hearts. Grapes and figs are healthy foods, but not available from thorns or thistles.

'Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles? Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit.' (verses 16-18)

To substantiate his warning against false prophets the Lord Jesus uses an illustration from creation. If you have good knowledge of nature you will often be able to recognise a tree from a distance by its shape and its leaves. But even someone who does not know nature as well as this will be generally able to identify a tree by its fruit. This is an illustration from daily life the Lord Jesus uses here.

The fruits are first of all the words of the prophets. True prophets of God also may fail in their manner of life and their deeds. Whereas false prophets are often characterised by an especially amiable nature. This is why the fruits in this case are not only deeds but particularly the teaching which is brought. By them the disciples of Jesus will recognise if the Spirit of God or a false spirit is speaking. The Word of God says: 'Try the spirits whether they are of God; because many false prophets are gone out into the world.' and 'He that abideth in the doctrine of Christ, he hath both the Father and the Son. If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed' (1 John 4:1 and 2 John 9-10).

Thorns and thistles are symbolic of what the ground brings forth as a result of the fall of the first couple. Surely no one expects refreshing grapes or figs, which the Old Testament refers to as signs of God's blessing (see Zech. 3:10), to come forth from such plants. No, only a good tree can bring forth good fruit, and only a corrupt tree brings forth evil fruit. The word 'evil' (or 'bad' in JND) is used in a figurative sense. The fish in Matthew 13:48 are probably not bad either but inedible.

There follows now a warning about false prophets, which is in very plain connection with that about the different roads which men were taking to reach a common end. This is intensified by the fact that, wherever the true Voice speaks, there will come the false voice after it, its mocking echo; like Jannes and Jambres opposing by imitation, putting on the dress of the sheep, but as a lure, over the evil heart within. The fruit would manifest them, but we must remember that this is not necessarily immoral conduct, in which the sheep's clothing would no longer remain, but rather their doctrines tested by experience, as when men looking for grapes find nothing but at most the mockery of these. Satan; when coming in as an angel of light, does not send out open evil-doers to commend his doctrines, while on the other hand an evil life may dishonor the preacher of substantial truth. But a true and needy soul, testing for itself the fruit of what is spoken, will assuredly find that the truth has its own witness to the heart and conscience, such as nothing but the truth can have. Here, above all, the Lord's words apply, that a good tree cannot bring forth bad fruit.

Our Lord continues: "By their fruits ye shall know them: do men gather grapes from thorns or figs from thistles? So every good tree bringeth forth good fruit, but the corrupt tree bringeth forth bad fruit. A good tree cannot bear bad fruit, nor can a corrupt tree bring forth good fruit. Every tree that bringeth forth not good fruit is cut down and cast into the fire. By their fruits then shall ye know them" (verses 16-20).

What does our Lord mean by fruit? Does He mean downright wickedness? There is no question that immorality and evil deeds are included under the term fruit. Many a false teacher began in teaching error in such a way that the error could hardly be distinguished from the truth, but continuing in error he ended with many of his followers in the flesh. Often behind the most subtle errors the flesh is nourished and an outbreak in gross immorality may follow. Yet, if our Lord meant nothing but evil deeds and wickedness, it would be hard indeed to detect these false ones. Satan is not so blind as to peddle his lies around by wicked people whose lives bear the stamp of immorality and open wickedness. He does it in quite another way. We were often told of people who hold the most abominable doctrines and deny the Deity of our Lord as well as the atonement, "But look at the beautiful lives they live! How meek and lovely they are! How much good they do! Do not their lives prove that their doctrine is right and the fruit show that the tree is not bad?" This outward moral appearance and a "sweet" temper belongs only too often to the sheep's clothing and is one of the devices of Satan with which he tries to lead many away from the truth and into error -- the fruit by which we shall know them may be wickedness in the grossest form, but it means more than that. The word "Do men gather grapes from thorns and figs from thistles?" is the key. Grapes and figs speak of true fruit. Thorns bear fruit which may resemble grapes, but never can they be grapes from which comes the wine which makes glad the heart of God and man. The soul looking deeper (and we remember the warning is for believers) than outward appearances finds soon that the false teacher or spirit is not in the truth. He tests it by the Word, and finds the fruit, the glory of Christ and glorying in Him, lacking. It is a most subtle substitute for the true fruit -- a counterfeit -- and leaves the soul empty. A believer, not much taught in the Scriptures, sent us a few weeks ago a question about a certain publication which was sent to him with the promise of leading him into a better knowledge of the Bible inasmuch as it was devoted to Bible study. We wrote him at once exposing the true character of the paper. He answered, that while he had but little knowledge yet of the Word, and while much seemed to be in favor of the paper which had been placed into his hands, yet while reading he experienced a feeling of emptiness, there was no response from his heart and a lack of joy and peace. This, perhaps, will be helpful to see how a true believer will know them by their fruit.

But in the words of our Lord we have also the most definite teaching of that doctrine, which may be termed the A B C of the Gospel, the total depravity of man, the utter ruin of man, and, therefore, the necessity of the impartation of a new nature. Both, as we well know, are denied by some of the leading preachers and teachers of all the great evangelical denominations. To deny these truths is equal to the denial that Christ is our Saviour. Man is, according to the new theology, his own Saviour. The tree is corrupt, the fruit is bad. That which is born of the flesh is flesh. The tree is good and the fruit is good. That which is born of the Spirit is Spirit.

They who love Christ do well to beware of false prophets, who are such as come unto them in the garb of sheep, but within are ravening wolves. They may cultivate sanctimoniousness and pretend to devotion, but are under the dominion of a mightier foe than themselves, and filled with the keenest zeal to deprive the Christian of a true Christ, of life eternal possessed, of present standing as God's righteousness in Christ, of association with Him in and for heavenly glory. Are not such truly ravening wolves? What remains, if the disciple lose all the treasure distinctive of Christianity?

"By their fruits ye shall recognise them." Do they exalt Him who humbled Himself? Do they confess His incomprehensible being, God and man in one Person? Do they proclaim His grace and truth? Do they follow Christ in absolute subjection to scripture? Do they own it, as the invaluable standard, and the sure communication, of God's mind by His Spirit? Is the believer established? Is the sinner won and delivered? Or are minds filled with ideas which but inflate the spirit, inspire self-complacency, and end in death? For these are practical effects which test what men teach, and which are legible enough to simple souls little versed in scriptural truth, and still less in human subtleties. And thus the Lord safeguards the sheep in various ways.

The warning against false prophets follows. They are to be known not by their fine words but by their fruits. Fruit is the result and crowning expression of life, and it reveals the character of the life that it consummates. The false prophet has a false life, which must reveal itself in false fruit.

But there are not only false prophets but false disciples — those who loudly profess allegiance to the Lord, but the vital link of faith is lacking. Vital faith, as the Apostle James tells us, must express itself in works. Everyone, who really comes under the lordship of Christ in faith, must of necessity be set to do the will of the Father in heaven, whom He presented. Judas Iscariot furnishes us with a terrible example of verses 22 and 23. Evidently he performed works of power along with the other disciples, but it was proved at last that no link of real faith ever existed and he was but a worker of iniquity.

From verse 43 the outward profession of discipleship is contemplated. The Lord may have had such an one as Judas specially in view, in speaking thus. Amongst those who took the place of being His disciples there might be found "an evil man," as well as "a good man." They are to be discerned by their fruits, seen in both speech and action. Nature is revealed in fruit. We cannot penetrate the secrets of nature either in a tree or in a man, but we can easily and correctly deduce the nature from the fruit.

This leads to the consideration that mere profession counts for nothing. Men may repeatedly call Jesus their Lord, but if there is no obedience to His word, there is no discipleship that He acknowledges. The kind of foundation that cannot be shaken under the testings is only laid by obedience. The mere hearing of His word apart from obedience may erect an edifice which looks like the real thing; but it means disaster in the day of testing.

The second part of the chapter is connected with this; for he begins his discourse on works, as proofs of faith, by speaking of this mercy which answers to the nature and character of God, of which, as born of Him, the true Christian is made a partaker. The profession of having faith without this life — the existence of which is proved by works — can profit no one. This is plain enough. I say the profession of having faith, because the epistle says it: "If a man say he has faith." This is the key to this part of the epistle. He says it: where is the proof of it? Works are the proof; and it is in this way that the apostle uses them. A man says he has faith. It is not a thing that we can see. I say therefore with reason, "Show it me." This is the evidence of faith which is required for man — it is only by its fruits that we make it evident to men; for the faith itself cannot be seen. But if I produce these fruits, then assuredly I have the root, without which there could not be the fruits. Thus faith does not show itself to others, nor can I recognise it, without works; but works, the fruit of faith, prove the existence of faith.

(V. 22). Here, then, we see not only works but that “faith wrought with his works.” It is evident, then, that while the Apostle speaks of works proving our faith, he refers, not simply to good works such as kindly nature can produce, but only such works as faith can produce. They are faith works; and by such works faith is made perfect. If, on the one hand, the Apostle insists upon works as the test of faith before men, on the other hand, he insists upon faith as the test of the works.

The Lord sets up a general principle which says that the quality of the tree is decisive for the quality of the fruit: 'Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit.' (verse 17) To stress this principle he adds that there are no exceptions: 'A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit' (verse 18). This principle from nature has a spiritual application. It is a simple but clear 'either ... or' which helps the disciple to discern the spring from which the message he is hearing is coming.