The Two Operating Systems: Flesh and Spirit Text: Romans 8:5-8
Introduction: The Great Divide
We live in an age that despises distinctions. Our culture is laboring with all its might to blur every line, erase every boundary, and flatten every mountain God has raised. They want to blend male and female, good and evil, truth and falsehood, light and darkness. The great project of modernity is to create a universal gray goo, a world where nothing is definitively one thing and not another. But the Christian faith is a religion of sharp, glorious, life-giving distinctions. And nowhere is that distinction more fundamental, more absolute, than the one Paul lays before us in this passage.
The apostle is not describing two slightly different personality types, or two competing self-help programs. He is describing two different kinds of humanity, two different operating systems for the soul. You are either running on the software of the flesh, or you are running on the software of the Spirit. There is no third option, no dual-boot system. One leads to death. The other leads to life and peace. One is in a state of perpetual, seething rebellion against God. The other is in a state of Spirit-wrought submission. You are in one of these two states as you sit here this morning.
This is not, therefore, a passage for us to merely nod along to. This is a diagnostic text. This is a spiritual MRI. Paul is putting the stethoscope to our chests to determine if there is a heartbeat of spiritual life, or the flatline of the flesh. And we must not misunderstand what he means by "flesh." He is not talking about your physical body, your skin and bones. The Bible does not teach that the material world is evil; God made it and called it good. The "flesh" (sarx in the Greek) is the principle of unregenerate human nature. It is humanity in Adam, humanity turned inward on itself, humanity trying to be its own god. It is the natural man, apart from the invasive, life-giving grace of the Holy Spirit. And the central point of this passage is to show us that this operating system, the flesh, is not just buggy. It is not just malfunctioning. It is, by its very nature, hostile to its Creator and completely incapable of pleasing Him.
This is the doctrine of total depravity, not that man is as bad as he could possibly be, but that sin has corrupted every part of him. His mind, his will, his affections, are all bent. They are all running on the wrong code. And so, the solution is not a software update. It is not a patch. The solution is that the whole hard drive has to be wiped, and a new operating system, the Spirit of God, must be installed by divine power.
The Text
For those who are according to the flesh set their minds on the things of the flesh, but those who are according to the Spirit, the things of the Spirit. For the mind set on the flesh is death, but the mind set on the Spirit is life and peace, because the mind set on the flesh is hostile toward God, for it does not subject itself to the law of God, for it is not even able to do so, and those who are in the flesh are not able to please God.
(Romans 8:5-8 LSB)
The Two Mindsets (v. 5)
Paul begins by showing that these two states of being, flesh and Spirit, result in two diametrically opposed orientations of the mind.
"For those who are according to the flesh set their minds on the things of the flesh, but those who are according to the Spirit, the things of the Spirit." (Romans 8:5)
The verb here, "set their minds on," is phronousin. It's more than just a passing thought. It describes a mindset, a disposition, a fundamental orientation. It's what you savor, what you value, what your internal compass is pointing toward. It is the default setting of your heart and mind. Your mindset determines your direction.
Those who are "according to the flesh" have their minds set on "the things of the flesh." What are these things? They are the concerns of a life lived as though God does not exist. It is a life centered on the self. This can manifest in crass, obvious ways, the works of the flesh Paul lists in Galatians 5: adultery, impurity, strife, envy, drunkenness. But it can also be very respectable. It can be a mind set on career advancement, financial security, public reputation, political power, or even religious observance, if these things are pursued for their own sake, apart from God. The fleshly mindset is any mindset that has man at the center. It is the operating system of autonomy.
In stark contrast, those who are "according to the Spirit" set their minds on "the things of the Spirit." What are these things? They are the things that please God. They are the fruit of the Spirit: love, joy, peace, patience, kindness. They are the realities of God's kingdom: righteousness, truth, and holiness. The spiritual mind is not one that is detached from the world, floating in some mystical haze. Not at all. The spiritual mind engages the world, but it does so with a Godward orientation. It asks, "How can I glorify God in my work? How can I love my neighbor in this transaction? How can I advance Christ's kingdom in this conversation?" The mind of the Spirit is the operating system of theonomy, God's law, which is to say, God's loving rule.
The Two Destinies (v. 6)
Next, Paul shows us the ultimate, non-negotiable outcome of each mindset. There are only two destinations on this spiritual railroad.
"For the mind set on the flesh is death, but the mind set on the Spirit is life and peace." (Romans 8:6 LSB)
Let the weight of this settle on you. The mindset of the flesh is death. It is not that it might, if left unchecked, eventually lead to death. It is death. It is a state of spiritual deadness right now. The man living in the flesh is a walking corpse. He is alienated from the life of God (Eph. 4:18). He might be breathing, eating, and paying his taxes, but he is spiritually dead. And this present state of spiritual death is simply the down payment on the final installment, which is eternal death, eternal separation from God.
The world does not believe this. The world thinks the fleshly mindset is life. "Live for yourself! Follow your heart! You only live once!" This is the gospel of the flesh, and its end is destruction. It promises freedom and fulfillment, but it delivers only bondage and decay. It is a baited hook. It is poison served in a crystal glass. The entire advertising industry is dedicated to catechizing you in the things of the flesh, and its constant sermon is that this path leads to the good life. Paul tells us it is a dead end. Literally.
But the mind set on the Spirit is life and peace. This is not just a promise for the future. It is a present reality. To have the Spirit is to have the life of God Himself dwelling in you. It is to be brought from death to life (Eph. 2:5). And with that life comes peace. First, there is peace with God, because the hostility has been ended by the blood of Christ. Our sins are forgiven, and we are declared righteous in Him. Second, there is the peace of God, an internal tranquility that comes from knowing you are right with your Maker, that your life is in His hands, and that He is working all things for your good. The world is frantically searching for life and peace in all the wrong places, and the Christian has it as a free gift through the Spirit.
The Reason for Death: Hostility and Inability (v. 7)
In verse 7, Paul explains why the mind of the flesh is death. He drills down to the root of the problem, and what he finds is not simple ignorance or weakness, but active, deep-seated rebellion.
"because the mind set on the flesh is hostile toward God, for it does not subject itself to the law of God, for it is not even able to do so," (Romans 8:7 LSB)
The carnal mind is not neutral toward God. It is not a blank slate. It is in a state of active warfare against Him. The word is echthra, meaning enmity, hostility. This is the native condition of the fallen human heart. Left to itself, the heart of man hates God. It hates His sovereignty, it hates His law, it hates His holiness. The natural man does not want a God to whom he must give an account. He wants to be his own god, the captain of his own soul, the master of his own fate. And so, he is at war with the true God who holds that position.
This hostility manifests itself in a refusal to submit to God's law. "It does not subject itself to the law of God." The law of God is simply the expression of God's character. It tells us how to live in a way that reflects our Creator. But the fleshly mind will not have it. It sees God's law not as a fatherly path to life, but as an intolerable restriction on its autonomy. It wants to write its own laws.
But Paul pushes it even further. It is not just that the fleshly mind will not submit. It cannot submit. "for it is not even able to do so." This is the heart of the doctrine of total inability. The unregenerate man is not a drowning man who just needs a life preserver thrown to him. He is a corpse at the bottom of the ocean. He has no ability within himself to please God, to obey God, or even to turn to God for salvation. He is spiritually dead, and dead men can't do anything. This is why Jesus said, "No one can come to Me unless the Father who sent Me draws him" (John 6:44). Salvation cannot be a cooperative effort between God and man, because one of the parties is a corpse. It must be a work of resurrection.
The Inevitable Conclusion (v. 8)
Verse 8 is the logical and inescapable conclusion of everything Paul has just argued. It is a thunderclap of theological reality.
"and those who are in the flesh are not able to please God." (Romans 8:8 LSB)
If the mind of the flesh is death, if it is hostile to God, and if it is unable to submit to His law, then it follows as the night the day that it cannot please God. Nothing that comes from the operating system of the flesh is acceptable to Him. Even the "good deeds" of an unregenerate person, their philanthropy, their civic-mindedness, their family devotion, are not pleasing to God. Why? Because they do not spring from a heart of faith and love for Him. They are not done for His glory. As the writer to the Hebrews says, "without faith it is impossible to please Him" (Hebrews 11:6). An act may conform outwardly to God's law, but if it is done from a heart that is hostile to God, it is a dead work. It is a filthy rag.
This is a devastating blow to all forms of human pride and self-righteousness. It tells us that we cannot earn our way to God. We cannot impress Him with our moral resume. We bring nothing to the table. Our only hope is for God to do for us what we cannot do for ourselves. Our only hope is for Him to rip out the corrupt hardware of the flesh and install the new life of the Spirit.
Conclusion: Reboot in the Spirit
So, where does this leave us? For the unbeliever, it should leave you in a state of desperation. It should strip you of all your self-confidence and show you your utter bankruptcy before a holy God. You are in the flesh. Your mind is set on death. You are at war with God, and you cannot win. You cannot please Him. Your only hope is to cry out for mercy. Your only hope is to plead with God to perform the miracle of regeneration in you, to give you a new heart and put His Spirit within you. You must repent and believe in the Lord Jesus Christ, who died to reconcile hostile enemies to God.
For the Christian, this passage is a profound comfort and a sober warning. The comfort is this: if you have the Spirit, if your mind is now, however imperfectly, oriented toward the things of the Spirit, this is not your own doing. It is a miracle of grace. God has done the impossible in you. He has taken a hostile enemy and made him a beloved child. He has taken a spiritual corpse and breathed into him the breath of eternal life. Your salvation is of the Lord, from start to finish, and therefore it is secure.
The warning is this: the old operating system, the flesh, has been uninstalled as the ruling principle of your life, but its corrupted files still remain. The battle between the flesh and the Spirit is the central conflict of the Christian life (Gal. 5:17). Therefore, you must be diligent. You must consciously and deliberately set your mind on the things of the Spirit. How do you do that? You steep your mind in the Word of God. You discipline yourself in prayer. You engage in fellowship with the saints. You actively starve the desires of the flesh and feed the desires of the Spirit. You are no longer "in the flesh" as your defining state, but the flesh is still in you, and you must mortify its deeds by the power of the Spirit (Rom. 8:13).
The great divide in all of humanity is not between rich and poor, black and white, educated and uneducated. The great divide is between those who are in the flesh and those who are in the Spirit. One is a dead-end street. The other is the path of life and peace. By God's grace, may we all walk in the Spirit, setting our minds on things above, where Christ is, seated at the right hand of God.