Here on earth, there are two parts of you: spirit and body. Spirit and body meet in the mind... and they wrestle. The apostle Paul ruminated on this before any of us,
"For we know that the law is spiritual, but I am of the flesh, sold under sin. For I do not understand my own actions. For I do not do what I want, but I do the very thing I hate." Romans 7:14-15
Everyday, we wrestle in some way when our body wants to react one way and our spirit the other. Our spirits know sin from righteousness, and subscribe to it...we agree that certain behaviors, thoughts and words are right and some are wrong. And yet we still sometimes choose wrong. In our frustration with the person in front of us on the road, the person on the other end of the phone line, or in a tension-filled disagreement with our spouse, neighbor, child or whoever, we react in a way that in a clearer moment, we would describe as wrong. Why? Jesus explained to Peter and two of His disciples when they failed to stay vigilant while He went to pray.
"And he came to the disciples and found them sleeping. And he said to Peter, “So, could you not watch with me one hour? Watch and pray that you may not enter into temptation. The spirit indeed is willing, but the flesh is weak.” Matthew 26:40-41
The body is weak. Dethatched from the spirit, the body is like an undisciplined toddler: it wants what it wants and it wants it now. It cannot be reasoned with. When it is mad or greedy or even sad it just... detonates into a full blown tantrum. Like the toddler, screaming on the floor of the cereal aisle in the grocery store, making a fool of itself... and disappointing, embarrassing, the parent who is in this analogy, the spirit.
Without the spirit, the body is enslaved to sin. Without the spirit, the body cannot exert any power over sin, over reacting in such a way that is unrighteous. It is the spirit which has the power to discipline the body. Jesus gifted us this power with His death, Romans 6:6. Let's return to Paul,
What then? Are we to sin because we are not under law but under grace? By no means! Do you not know that if you present yourselves to anyone as obedient slaves, you are slaves of the one whom you obey, either of sin, which leads to death, or of obedience, which leads to righteousness? But thanks be to God, that you who were once slaves of sin have become obedient from the heart to the standard of teaching to which you were committed, and, having been set free from sin, have become slaves of righteousness. I am speaking in human terms, because of your natural limitations. For just as you once presented your members as slaves to impurity and to lawlessness leading to more lawlessness, so now present your members as slaves to righteousness leading to sanctification.
Just as the body readily answered its master, Satan, so the spirit readily answers its master, God. And since the two are, for now, inextricably linked, this is where they wrestle. And they wrestle in the mind, therefore we must discipline the mind. God preserved a whole book of blueprints on how to do that. He explained that it requires selflessness, perseverance, and even suffering sometimes. Paul explained it to us in a tangible way:
Do all things without grumbling or disputing, that you may be blameless and innocent, children of God without blemish in the midst of a crooked and twisted generation, among whom you shine as lights in the world, holding fast to the word of life, so that in the day of Christ I may be proud that I did not run in vain or labor in vain. Philippians 2:14-16
Moment by moment, in the midst of an imperfect world, from within and imperfect body, we need to grip onto the word of life in order to choose the response, the action that would make Christ proud. Maybe that means we will need to be slower to speak, because we may need those crucial few moments to collect ourselves, to redirect ourselves toward the light when the body was primed to run toward darkness. God understands that we will feel angry (etc. negative emotions)... we are asked to hesitate before we react angrily.
Know this, my beloved brothers: let every person be quick to hear, slow to speak, slow to anger; for the anger of man does not produce the righteousness of God. James 1:19
The book of James is a great example of the way to discipline the body with the mind. It encourages steadfast faith and obedience to God. Reliance on spiritual provision from God. It reminds us that we can request support and direction and wisdom from God when we need it, when we ask with faith that He can provide.
Nobody wants to be, or to be known, remembered, as a person with a short fuse, hot temper, or reliably destructive. We want to be known as patient and wise and reasonable. We do not want to be remembered as the one who flipped off the driver beside us or the person who cursed (in our day, cussed) the person on the other end of the phone. Patient, wise, reasonable people put in the work to be that way. They understand that resolution comes from God, rather than from detonation.
The toddler's/ body's tantrum could result in this way: they get what they want and are temporarily assuaged; their unreasonable behavior, seeming to have worked, is inculcated into them and they develop a proclivity for such behavior in the future. As they age, their behavior is less and less acceptable and less and less manageable.
Or the toddler's / body's tantrum quits wailing long enough to be reasoned with. They thing that it want harmful to themselves and/or others and unproductive for their growth, physically, spiritually, mentally, etc. Bad behavior is always unproductive for the situation as well; we fail to achieve the result we want when we react hotly. If we cannot reach the peach, should we roast the tree?
God sent Paul to encourage us to denounce the body, sin, Satan, as our master, Acts 26:18; to pronounce God as our master. And he presents a very blessed case for why it would be better to discipline our body and allow our spirit to choose its master instead:
For when you were slaves of sin, you were free in regard to righteousness. But what fruit were you getting at that time from the things of which you are now ashamed? For the end of those things is death. But now that you have been set free from sin and have become slaves of God, the fruit you get leads to sanctification and its end, eternal life. For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord. Romans 6:20-23
The end result we desire is achieved when we allow God to direct our mindset and our movements. Whatever worldly thing body wants, it is to fill a void that cannot be quenched by the world. It certainly cannot be quenched by worldly methods. The body wants to be beautiful or powerful or intelligent or praised... those things only come from a disciplined mind and an in-control spirit. Those things only come from God; the spirit needs to be in-control in order to be a faithful conduit through which God's spiritual provision comes and satisfies all of the needs of the individual in healthy, steadfast, productive, blessed ways.
2 Corinthians 5:7 is our example to walk by faith, not by sight. Among other things, that means we should allow our spirit to lead, not our body. We should rely on our spirit to describe the situation, not our body. The body is, by nature, self-centered. The spirit, when the mind is disciplined, it able to be more objective. It does not 'fly off the handle'; it is reasonable because it is patient, observant, honest and dependent on God. It is more aware of the whole picture, more skillful with the problem, more empathetic toward the underdeveloped, underdisciplined mind with which they spar. It understands that God, and Jesus's methods, are more productive than the body could ever be.
Yes: Every day, in many moments, our body wrestles with our spirit. The self we, and Jesus, would be proud of can win! Our spirit will win when we dedicate our minds to God's instruction and Jesus's example. Conversation by conversation. Action by action. Thought by thought. Moment by moment.