The Undivided Heart: Your Treasure, Your Vision, Your Master Text: Matthew 6:19-24
Introduction: The War for Your Worship
We have come to a section of the Sermon on the Mount that functions like a spiritual diagnostic center. Here, the Lord Jesus lays out a series of tests to reveal the true condition of our hearts. And we must understand that this is not gentle, therapeutic advice for a more fulfilling life. This is a declaration of war. It is a line drawn in the sand between two mutually exclusive kingdoms, two ultimate allegiances, and two eternal destinies. The modern world, and sadly much of the modern church, wants to believe we can negotiate a peace treaty between these two kingdoms. We want to live in the suburbs of the Celestial City while maintaining a profitable business address in Babylon.
But Jesus tells us this is impossible. The central issue of human existence is the issue of worship. Who, or what, will you serve? What will you treasure? What will you fix your gaze upon? Every human heart is an altar, and something is always being sacrificed upon it. The choice is not between worship and non-worship; the choice is between the living God and a host of idols that promise the world and deliver only damnation. In our text, the Lord focuses on the chief rival to God in the hearts of men, a rival deity He calls Mammon.
Mammon is not simply money. Mammon is wealth personified. It is the entire system of worldly security, status, and power that sets itself up as a provider and protector in the place of God. It is the spirit of materialism. And our culture is utterly saturated with its worship. We are taught from the cradle to measure our lives by what we own, what we earn, and what we can acquire. Jesus cuts through all this with a surgeon's scalpel. He tells us that our financial portfolio is a theological document. He tells us that our eyesight is a moral issue. And He tells us that our employment status before God is an all-or-nothing proposition. You are either a wholehearted servant of the living God or you are a slave to a false one. There is no third option.
The Text
"Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal. But store up for yourselves treasures in heaven, where neither moth nor rust destroys, and where thieves do not break in or steal; for where your treasure is, there your heart will be also. The eye is the lamp of the body; so then if your eye is clear, your whole body will be full of light. But if your eye is bad, your whole body will be full of darkness. If then the light that is in you is darkness, how great is the darkness! No one can serve two masters; for either he will hate the one and love the other, or he will be devoted to one and despise the other. You cannot serve God and wealth."
(Matthew 6:19-24 NASB)
The Great Treasury Decision (vv. 19-21)
Jesus begins with a fundamental command regarding our investments. This is about where we place our ultimate hope and security.
"Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal. But store up for yourselves treasures in heaven..." (Matthew 6:19-20)
Notice the two treasuries. The first is the earthly treasury. Jesus is not condemning possessions, savings, or prudent planning. He is condemning the act of "storing up for yourselves," the hoarding impulse that seeks its ultimate security and identity in material things. He gives us three reasons why this is the height of folly. Your earthly treasures are subject to moth, rust, and thieves. Moth represents the slow, organic decay of things like fine clothing or textiles. Rust represents the slow, inorganic decay of things like metal, our cars, our tools, our buildings. Thieves represent sudden, catastrophic loss, whether through theft, a stock market crash, or rampant inflation. The point is this: every single earthly treasure is temporary. It is all heading to zero. To place your ultimate hope in something that is guaranteed to fail you is not just bad strategy; it is insanity.
The alternative is the heavenly treasury. This is the only investment portfolio with a guaranteed eternal return. So what are these treasures? They are not celestial stocks and bonds. Heavenly treasure is accrued on earth through acts of faith and obedience that have eternal value. It is the cup of cold water given in Jesus' name. It is faithfulness in your vocation done for the glory of God. It is generosity to the poor and support for the work of the gospel. It is every act of secret righteousness, as Jesus has just discussed, that seeks no earthly reward. These investments are secure because they are lodged in the character and promise of God Himself. They are beyond the reach of decay and disaster.
Then Jesus provides the underlying principle, the spiritual law that governs this reality:
"for where your treasure is, there your heart will be also." (Matthew 6:21)
This is one of the most important diagnostic statements in all of Scripture. We tend to think this works the other way around, that we invest in what we love. Jesus says it is more profound than that: your heart follows your treasure. Your affections are dragged along behind your investments. Do you want to love the things of God more? Then invest your time, your energy, and your money in the things of God. Do you find your heart growing cold, worldly, and anxious? Check your bank statements. Check your calendar. They will preach a sermon to you and tell you exactly where your treasure is, and consequently, where your heart is.
The Organ of Perception (vv. 22-23)
Jesus now moves from the metaphor of a treasury to the metaphor of the eye. He is connecting our external investments to our internal vision.
"The eye is the lamp of the body; so then if your eye is clear, your whole body will be full of light. But if your eye is bad, your whole body will be full of darkness." (Matthew 6:22-23a)
The eye is the organ that lets light into the body. Metaphorically, it is the faculty of spiritual perception. It is how you see and interpret reality. A "clear" eye, or a "single" eye, is one that has a single focus. In this context, it is an eye fixed on God and His kingdom. When your ultimate goal is singular, to glorify God, then your whole life, your "whole body," is filled with the light of truth, clarity, and purpose. You see things as they really are. You can evaluate the world correctly because you are looking at it from God's perspective.
But a "bad" eye is a divided eye. It is an eye that is trying to look in two directions at once, at God and at Mammon. This is the eye of the man who wants to serve God, so long as it doesn't interfere with his financial ambitions. This double vision does not result in a little bit of light; it results in total darkness. Your entire life becomes filled with confusion, anxiety, and moral compromise. You cannot see straight. You call evil good and good evil. And Jesus adds a terrifying conclusion:
"If then the light that is in you is darkness, how great is the darkness!" (Matthew 6:23b)
What does this mean? It means that if the very faculty you have for perceiving truth, your spiritual "eye," is itself corrupted by greed and double-mindedness, then you have no way of knowing you are in the dark. You are blind, but you think you can see. This is the spiritual condition of the Pharisee, and it is the condition of every self-deceived materialist. It is a profound, damnable darkness because it is a darkness that masquerades as light.
The Two Masters (v. 24)
Finally, Jesus drops the metaphors and states the principle with stark, unavoidable clarity.
"No one can serve two masters; for either he will hate the one and love the other, or he will be devoted to one and despise the other. You cannot serve God and wealth." (Matthew 6:24)
This is the bottom line. The relationship we have with our ultimate value is not one of casual preference; it is one of servitude. You are a slave to what you treasure. And you can only have one master. Jesus says it is psychologically and spiritually impossible to serve two. Attempts to do so will inevitably lead to a choice. You will end up loving one and hating the other. You will be devoted to one and despise the other. Notice the strong, emotional language: love and hate, devotion and contempt. There is no neutrality in the war for your worship.
And the two masters are God and "wealth," or Mammon. As we said, Mammon is the personification of material riches as a god. Mammon makes promises. It promises security, which only God can give. It promises significance, which only God can bestow. It promises happiness, which can only be found in God. To serve Mammon is to organize your life around the acquisition of wealth. It is to trust in your 401(k) more than you trust in the providence of your heavenly Father. It is to make decisions based on financial gain rather than on faithfulness to God's Word. And Jesus says you cannot do both. You cannot serve God and Mammon any more than you can face north and south at the same time.
Conclusion: The Liberating Gospel
The diagnosis here is severe. We are all born with a natural inclination to serve Mammon. Our fallen hearts are idol factories, and Mammon is one of the chief products. We are born treasuring the earth, with bad eyes, and with a natural allegiance to the wrong master. So what is the solution? It is not simply to try harder to be generous or to squint until our vision clears up.
The solution is the gospel. The gospel tells us that we have a treasure that can never be lost. "For you know the grace of our Lord Jesus Christ, that though He was rich, yet for your sake He became poor, so that you through His poverty might become rich" (2 Corinthians 8:9). Our true wealth is in Christ. He is the pearl of great price, for whom a wise man sells all that he has to acquire Him.
When the Holy Spirit opens our eyes to see the surpassing worth of Jesus Christ, our spiritual vision becomes "clear" for the first time. We see that He is the only treasure worth having. And when we treasure Him above all else, our hearts are captured by Him. We are transferred from the service of our old master, Mammon, to the joyous, liberating service of our new Master, God.
This is what frees us to be truly generous. We no longer need to hoard earthly treasures for our security because our security is in Christ. We can hold our possessions with an open hand because our true inheritance is "imperishable and undefiled and will not fade away, reserved in heaven for you" (1 Peter 1:4). The Christian life is a life of joyful detachment from the world's trinkets because we have been given the kingdom. Therefore, the call of this text is a call to repentance. Repent of your love affair with Mammon. Repent of your double-mindedness. Ask God to give you a single eye, one that sees the supreme glory of Jesus Christ. For when He is your treasure, your heart will be in the right place, your vision will be clear, and you will be the glad servant of the only Master whose service is perfect freedom.