What did Jesus mean when He said the eye is the lamp of the body (Matthew 6:22)?

And this alone gives a single eye: there is no confusion, no distraction of vision; no unsteadiness therefore, or uncertainty. The eye is the lamp of the body; not the light, but what holds and fixes the light. The light comes from elsewhere: the organ of perception does not create the light, but receives it. The light for us is in the Word alone: it is this that judges and makes plain; but there must be spiritual reception and, for this, capacity of reception, which the Lord indicates here, as it is stated by the apostle (Eph. 1:18, R.V.) to be in the heart and its condition. With the heart set on things above, the eye is single and clear: God is before it, and in His light we see light. Then the whole body becomes full of light: the hands and feet have plenty of it for work and walk. On the contrary, if the eye be evil, the very light may blind one; and when the word of God becomes this, how great may the resulting darkness become.

"The lamp of the body is the eye; if therefore thine eye be single, thy whole body will be light; but if thine eye be wicked, thy whole body will be dark. If therefore the light that is in thee is darkness, how great the darkness!"

It is a question not of the light, which is perfect but of "the eye." Spiritual condition has an immense deal to do with the disciples seeing aright. Our recipiency and discernment, our actual judgment and our practice, depend on the state of our affections. The Lord presents the ready and effectual test. "If therefore thine eye be single, thy whole body will be light; but if thine eye be wicked, thy whole body will be dark."

Christ truly the object before one gives singleness of eye; and where He is simply and exclusively the "one thing" before the soul, the whole body is light. Difficulties vanish. The will of God becomes quite clear. I am surprised and ashamed to have had doubts here and uncertainty there. I recognise to my humiliation that I had been asleep in my ways and had to rise up from among the dead, and then only have Christ shining upon me.

The believer's eyes are to be far above the world's level: his true treasure is not material, but of eternal value, nor can it be corrupted or stolen. Today we know that treasure to be vitally connected with Christ Himself raised from the dead and seated in the heavenlies. Is not our heart there too? As we value those things that are eternal, and live and act in view of this, we shall be laying up treasure in heaven.

This gives a single eye, not the duplicity of seeking two contrary things. The eye is the lamp of the body, that is, the receptacle of the light. The light is altogether of God, and to receive that light with singleness of heart, having the one object of rightly sustaining the light, will result in our whole body being full of light, light for our walk, our works, our words, indeed for every department of our existence. This implies simplicity of faith (not duplicity).

But if the eye is evil, perverting what light it receives, there will be no light whatever in the body. In this case the light received is adroitly turned into darkness, a darkness that is "how great!" God's truth must not be trifled with: if perverted, it can plunge one into a state worse than that of ignorance.

'The light of the body is the eye.' In the two previous verses 19 to 21 the Lord Jesus spoke of two kinds of treasures the human heart may hang on to. Now he is talking about two kinds of 'heart-conditions'. He therefore uses the picture of the eye and this again he compares to a lamp.

Lamps are used to give light. Now we cannot say of the eye that it gives light but rather that it takes in the light. The parallel drawn by the Lord Jesus between the lamp and the eye is that the functioning of a shining lamp and that of a good eye lead up to similar results: both of them help men to recognise their surroundings. The better the lamp the brighter the lamp shines and the better the eye the better one can see. Of course the opposite is just a true: as a bad lamp gives poor light so a man with bad eyesight or even blind eyes is not able to see much or even nothing at all. This will be very detrimental to his whole body. Such is the first meaning of the introductory words of the Lord: 'The light of the body is the eye.'

But the Lord Jesus does not teach his disciples about the human eye but rather about the heart which he did already mention in verse 21: 'For where your treasure is, there will your heart be also.' In Scripture the eye is very often used to depict the inner condition of men. The Word of God speaks of 'haughty eyes' (JND) and of 'high looks' (Psalms 18:27; 101:5), of 'blinded eyes' (1 John 2:11), of 'eyes with no fear of God' (Psalm 36:1), of 'evil eyes' (Matt. 20:15; Mark 7:22) and of 'eyes that are not satisfied with riches' (Eccles. 4:8), but also of 'enlightened eyes' (Psalm 19:8) and of a 'bountiful eye' (Pro. 22:9).

'If therefore thine eye be single, thy whole body shall be full of light.' The word 'single' must be understood as 'plain, pure'. In the whole New Testament it only appears here and in the parallel-reference in Luke 11:34-36. The corresponding noun 'singleness' (JND: simplicity) appears more often. Ephesians 6:5 and Colossians 3:22 speak of the singleness of the heart and in 2 Corinthians 1:12 and 11:3 of the simplicity before God and the Christ. These references show clearly what the words 'single' and 'simplicity' mean. It is the simplicity and singleness of the heart marked by love and confidence which will not suffer any sin (and be it doubting or wicked ulterior motives) to mar our relation with our Lord and our God and Father. If the look of our eyes is unclouded the whole body will be profiting of it and if the heart is single towards Christ the spiritual life will be full of light. This very light has it's source in God. It helps the youngest believer to understand the Word of God and to put it into practice in his life. It gives clarity and strength to follow a path step by step. It helps us in the difficulties of life (which will not be spared to any disciple of the Lord) to recognise his leading and his hand in them. He will bestow this divine light upon every disciple of his who has the sincere desire to follow him in faithfulness and whose heart is filled with 'the simplicity as to the Christ' (JND).

The Lord Jesus mentions the expression 'an evil eye' in other connections also (see Matt. 20:15; Mark 7:22). There the evil eye is the visible proof for an envious, jealous heart. If our heart is filled with envy, pride or other evil things then our entire life is, so to speak, 'clouded' with darkness. We do not only deprive ourselves of every true joy in the Lord but we also loose the discernment as to ourselves and our surroundings. This is the significance of the figurative words of the Lord: 'But if thine eye be evil, thy whole body shall be full of darkness.'

'If therefore the light that is in thee be darkness, how great is that darkness!' Each born again disciple of the Lord has received the light of life by God. This light enlightens his own life and it shines as a testimony for God. In order for it to shine the heart needs to be single. But if the heart of the believer is filled with evil thoughts darkness does indeed prevail instead of light. The light which is in the believer has so to speak become darkness.

"Lay not up for yourselves treasures upon the earth." Here our Lord contrasts the heavenly with the earthly, the spiritual with the natural, the things of time with those of eternity. His estimate of these is perfect, and He would have us governed by that. The heart follows that which is most highly prized, and if it be the things of earth how great is the loss! Many artificial contrivances are got up to give security in this world where death lies upon all, but there are no insurance societies called for in regard to what is heavenly and eternal — eternal things are the sure things. Spiritual treasures are laid up for eternity, and to have heaven and eternity in view gives clearness of vision. The danger here is that selfishness may darken the moral sensibilities and weaken the character in such a way that power for decision is lost.

"The lamp of the body is the eye." This would indicate the organ of spiritual sight, the single eye denoting uprightness of motive with unity of purpose. "One thing I do." The body gives expression to the inner state, and in walking with God a person becomes an influence for good; where this is not, there is wavering like a double-minded man who is unstable in all his ways.

In our gospel, however, the light of the body is not that of the sun, but the eye: because the subject matter is the state of him who receives light from God, and not its manifestation in Christ. It is the eye, the organ of our moral vision; it is the aim and object of the heart. All depends on what is really before the soul when it is a question of seeing clearly. It is certain that all is right in Christ, and that there is enough grace in Him to cause the light to jet out. But morally the light is the eye; and it is important that the light which is in us be not darkness. It is not a question either of ourselves or of a sign from heaven. Faith is not founded on miracles: if its only basis is signs, evidences, etc., it is worth nothing; if it is not a conviction in the conscience, it is not the life of God. Christ had confidence in nothing of the kind (John 2:24-25). "My sheep hear my voice," instead of seeing miracles, and so believing.

It was not because there was no light shining. Men do not light a candle in order to hide it, as verse 33 says. The Lord had come into the world as the great Light and His beams were shining upon men. What was wrong was wrong, not with the light but with the eyes of men. This is emphasized in verses 34-36. The sun is the light of our bodies objectively: but our eyes are light to us subjectively. If the sun went out, there would be universal darkness, but if my eye went out, there would be absolute darkness for me. If my spiritual seeing faculty be evil, my mind is full of darkness: if single, all is light. In other words, the state of the one upon whom the light shines is of great importance. The state of the people was wrong, hence their insensibility to the light that shone in Christ.

Very searching words as to earthly possessions are next spoken. No tendency is more deep-seated with all men than that of pursuing, grasping at, and laying up treasures upon earth, though they waste under the action of natural forces as well as the action of violent men. If we really know the Father in heaven, we shall find our treasure in heaven, and there our heart will be; and we have only to have the single eye to see this, and to see all else clearly. Then too our bodies become full of light: that is, we become luminous ourselves. We shall either be dominated by God or by mammon, for we cannot serve two masters. God and mammon are too utterly opposed for that.