What did Jesus say about the heart?

In reply to the questions put to Him in the house, the Lord declared to his disciples (1) what was the root, and (2) what were the fruits of evil in men. The root was the evil thought of the heart, and the fruits were the specific acts of wickednesses some of which He named. In the evil thought therefore the evil deed is contained in embryo. Jesus said to them, "From within out of the heart of men evil thoughts proceed… .;" then He enumerated a list of some of the vile deeds which spring from man's inner motives, adding, "all these evil things proceed from within, and defile the man."

Evil thoughts. These are the inward reasonings and debates of man's mind. Within himself he deliberates, he calculates, he plans his schemes of sinful indulgence or wilful rebellion. "Things come into his mind, and he devises an evil device" (Ezek. 38:10; Micah 2:1-2). Thus, in describing the appalling moral degradation of the human race, the apostle traces it to this inward source: "knowing God they glorified him not as God, neither gave thanks; but became vain in their reasonings [thoughts] and their senseless heart was darkened" (Rom. 1:21). Hidden within the heart, it is one of man's strange delusions that his thoughts are thereby concealed from Omniscience, yet it is written, "The Lord knows the thoughts of the wise that they are vain" (1 Cor. 3:20; Ps. 94:51). The incarnate Son possessed and displayed this omniscience; indeed, according to the word of Simeon to Mary, one of the purposes of His mission was that "the thoughts of many hearts might be revealed" (Luke 2:35).

In Matt. 15: we have two hearts revealed to us — the heart of man and the heart of God. In reply to the Pharisees' criticism of His disciples for eating with unwashed hands, our Lord laid down that a man is not defiled by that which goes into his mouth, but by that which comes out, the words being the expression of what is in the heart. He proceeded to draw an appalling picture of the human heart. According to His judgement, which cannot err, it is a pestilent sink of iniquity.

The disciples had to ask Him privately concerning it, and in verses 18 to 23 we have the explanation. Man is corrupt in his nature. What comes from his very heart defiles him. Out of his heart proceed evil thoughts which develop into every kind of evil action. This is the most tremendous indictment of human nature ever uttered. No wonder the Pharisaic heart was far from God; but what a terrible thing that men with hearts like this should profess to draw near and worship Him.

(Vv. 14-16). Having exposed the hypocrisy of the outward religion of the flesh, the Lord, in the hearing of "all the people," shows that the source of defilement is not from without, but from within. The washing of hands and cups and pots, simply deals with defilement from without, but the source of moral defilement springs from the inward evil of the heart. This cuts at the root of all worldly religion of the flesh which simply deals with externals and leaves the heart untouched. God works from within and deals with the conscience and heart. The real source of defilement is not a man's environment but himself. It is true that man being such as he is — a fallen creature — if he goes into scenes of evil and temptation, his surroundings will stir up his lusts within. But even so the source of the evil is from within. An Angel can pass through Sodom and not be defiled, but not so Lot. There was no evil heart in the Angel to answer to sin; there was in Lot.

(Vv. 17-23). Alone with His disciples the Lord enlarges upon this theme, and interprets His illustration. Moral evil has its root in the heart whatever form the evil may take, whether it be evil thinking, evil acts, such as adulteries, murder, thefts or deceit, evil looking, or evil speaking in blasphemy, pride and foolishness. "All these evils come from within, and defile the man."

Hence the Lord pronounces them a generation of vipers. "The tree is known by his fruit." It was a bad tree, and no good fruit would He expect from it. "O generation of vipers," He adds, "how can ye, being evil, speak good things? For out of the abundance of the heart the mouth speaketh. A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things. But I say unto you, That every idle word (that is, I suppose, everything betraying contempt for God) that men shall speak, they shall give account thereof in the day of judgment. For by thy words thou shalt be justified, and by thy words thou shalt be condemned" (vers. 34-37). What God insists upon is testimony to Jesus. These idle words betray the heart's rejection of Jesus, and slight the Holy Ghost's testimony to Him. "By thy words thou shalt be justified, and by thy words thou shalt be condemned." It is with the mouth that confession is made unto salvation; and the words that leave out Jesus prove that the heart prefers its sin to Him. The words of the mouth evidence the state of the heart. They are the outward expression of the feelings, and they show a man in one way as much as his conduct does in another. If the heart is evil, the words are evil, the conduct is evil: all therefore comes into judgment.

The Lord in these verses is striking at people's pretense of goodness, while their hearts are untouched by His grace, unregenerate, and therefore still under sin. A good person is one whose heart is purified by faith in the Son of God, for by nature "there is none good, no not one" (Rom.3:12). Only the grace of God can make a difference in the person. In this case a "good treasure" is implanted in his heart, the treasure of the knowledge of the glory of God in the face of Jesus Christ, communicated to "earthen vessels" (2 Cor.4:6-7). Only good can come from this, however weak the vessel may be. Without this good treasure a person has only "an evil treasure" in his heart and his mouth soon expresses this, for what is predominant in the heart, his mouth will speak.

As violence then was judged and excluded in any shape for the disciples, so was impurity. The avoidance of the extreme act might satisfy a Pharisee or Scribe; but the Lord could not dispense with anything short of truth in the inward parts. To look at a woman lustfully was to commit adultery with her already in his heart; and it is not the outside only that God regards but the heart above all. It is only a new nature that delights in holiness; and he who has it by grace answers to the will of God his Father; and abhors himself if he slip even into a wrong look, as unworthy of his calling and hateful to Him who loves him.

The moral condition of the heart or soul, is here the important question. God only being pure absolutely, there must be purity of heart to appreciate Him. There is no thought here, we need scarcely say, of bodily sight, for even Jesus is now hidden from our view. It is only with the eyes of the heart or the moral vision of the soul — which is simply faith — that we can see God or appreciate His excellency and glory; and this blessedness is made to depend on the condition of the heart. "Blessed are the pure in heart, for they shall see God." The purer the heart is, the more clearly it will see God, and the more clearly it sees God, the purer it must become. Thus the one acts and re-acts upon the other.

The heart will be where our treasure -- what we count as valuable -- is. The treasure in the heavens is certainly Christ, for whom we may wisely "suffer the loss of all things," as Paul expressed it (Phil.3:8). For what sensible person would not be willing to lose what he cannot hold anyway, in order to gain what cannot be lost for eternity?

As I have said, among many deeply-precious lessons which this portion teaches us, there are three points which especially demand our attention. Firstly, our Lord's earnest desire, that during this period of His absence from us, we should be in the habit of looking to Him about everything, and to expect all we need from Him. He was going to the Father. Though away from us as to personal presence, there would be no change in His love or His care. Nor would His power be less; for He was going to the position of all power in heaven and in earth. He therefore first of all makes a particular request before leaving them; it was this, that they would exercise faith in Him, and not allow their hearts to be troubled. How exquisitely tender this is! What loving concern and interest it manifests! Did the precious Saviour say, You will not have trouble? No. Quite the contrary. He said, "In the world ye shall have tribulation;" but twice in this chapter He entreats us not to let our hearts be troubled. How is it possible that my heart should not be troubled, some may say? Jesus supplies the answer. As Jews they had known what it was to believe in God, to trust God; but now they were also to trust Him, exercise faith in Him. "Believe also in me." How simple and efficacious is this preventative of heart-trouble! Do we know its blessedness, beloved, in our own soul experiences? Do we so cast all our care upon Him, who careth for us, as to keep our troubles as it were at arms' length, so as not to get under them? How sweet and salutary is this counsel! This trust in Him is something more than believing on the Lord Jesus for salvation; for it is because we are His own, and objects of His everlasting love and care, that we are enjoined to roll every burden upon His Almighty arm, and leave it there. "Believe also in me." How blessed, then, the thought, that the Lord Jesus, though now in glory, far above all principality and power, desires that in this present trying scene our eyes may be looking to Him, and casting every trouble into His arms of love, so that our poor hearts may be free to love and serve Him, and not be oppressed by grief; but instead of this, as we afterwards read, that His peace in all its calm unruffled sweetness may be ours. I repeat, how loving is our Lord's counsel, and how marvellous His care for our present comfort and blessing in Himself!