There is no such thing as a “sin nature.” The Bible never refers to the “sin nature.” It is a myth of modern theology. However, the Bible DOES teach a lot about the “flesh.” This study looks at Romans 6:19 (and other passages from Romans) to learn what the flesh actually is, and what we are to live in the Spirit rather than in the flesh.
Note that this study is an excerpt from my Gospel Dictionary online course. This course considers 52 key words of the Gospel and thousands of biblical texts. The course contains over 100 hours Bible teaching. You can take the course by joining my online discipleship group.
So let us see what we can learn about the flesh from Romans 6:19 and other texts.
The Flesh in Romans 6:19
I speak in human terms because of the weakness of your flesh …
For when we were in the flesh, the sinful passions which were aroused by the law were at work in our members to bear fruit to death.
… So then, with the mind I myself serve the law of God, but with the flesh the law of sin.
For to be carnally minded is death, but to be spiritually minded is life and peace. Because the carnal mind is enmity against God; for it is not subject to the law of God, nor indeed can be.
The concept of flesh is prominent in the Pauline epistles. In general, when Paul refers to the flesh, he is referring to “the whole of man’s physical existence” (TDNT, VII:125). This not only includes the tissue that makes up the body, but also a person’s mental capacities, inner anxieties, and physical strength. For Paul, the term flesh “describes earthly life in its totality” (TDNT, VII:126).
As a result of this way of thinking, Paul frequently differentiates between the earthly life of the flesh and the heavenly life of the Spirit. The earthly life is not inherently evil or hostile to God; it is simply limited in its scope and understanding. The early life of the flesh lacks all of the information needed to make proper decisions about what is important in life and how to understand the events of life.
So, for example, when Paul writes in Romans 6:19 about speaking in human terms because of the weakness of the flesh, he is simply saying that he is describing how life works from physical, earthly, and human perspective. When humans sin, we do not think we are giving up our freedom to the sin. To the contrary, sin often seems quite liberating. But Paul point out that this is only because of the weakness of our flesh (or mind, in this case), to understand what is really happening.
We only gain proper perspective about slavery to sin and freedom in the Spirit through the regeneration that comes as a result of the indwelling Holy Spirit (Romans 6:1-14). The spiritual awakening and understanding that comes through Spirit baptism helps us see the world, ourselves, and our slavery to sin in a whole new light. Prior to this awakening, the flesh is unable to fully comprehend or grasp the danger of giving ourselves over to sin. But the way of slavery to sin is the way that leads to death (Romans 6:21-23).
This concept of ignorant flesh leading to sin and death is further explained in Romans 7.
The Flesh in Romans 7:5, 25
In Romans 7, Paul also shows how the law works together with the flesh to bring about sin and death. The flesh, being ignorant of the ways of the Spirit, loves to focus on externals as a way to determine what is right and wrong. The law is only concerned with external actions and behaviors. One can keep the whole law, and yet still not have the true, inner change of heart that is wanted and desired by God. This is why God did not want or desire to give the law to the people of Israel. He wanted a relationship based on love, rather than a religion based on law.
But when the law is followed in the blindness of the flesh, it leads a person to think that they are doing what God wants, and are therefore, “in the right” with God. It further allows people to judge, accuse, and condemn other people for not obeying the law. Such condemnation and accusation leads them into a life of death. They themselves do not accomplish what God actually wants in life, but instead die to His purposes and plans for them.
Furthermore, as a result of their judgment of law-breakers, they feel justified in their zeal to call for the condemnation and killing of people whom they view as the enemies of God. The law and flesh work together to create a religion based on death. The “sinful passions” that Paul speaks of in Romans 7:5, therefore, are not primarily the passions of lust and sensuality, but the zealous passions of religion which lead people to kill and condemn in God’s name.
In Romans 7:25, Paul contrasts the law of God with the law of sin. His mind, that is, his spiritual mind, serves the law of God, but his flesh serves the law of sin. Paul has already pointed out that the law of sin is the religious Mosaic Law that is based on externals. This means that the law of God cannot be the same as the religious law. Rather, the law of God is a spiritual law written upon the heart of the regenerate person. It is not based on a list of things to do, but on a relationship of love for God and others.
The Flesh in Romans 8:6-7
As a result of living according to the law of God, all condemnation and accusation is done away with. We are not condemned; nor do we condemn (Romans 8:1-8). It is only the fleshly, carnal mind that is still focused on the externals of the religious law of sin that condemns and accuses others. This way of life, as Paul already stated, leads only to death for all involved.
But true life and liberty is found by allowing the Spirit to work with our mind and show us what God really wants for us in life (Romans 8:6-7). We live our best life when we do not allow our fleshly mind with its limited perspective to rule and dominate, but instead allow the illuminating Spirit to guide our thoughts and actions so that we love, accept, and forgive others, just as God loves, accepts, and forgives us (Romans 8:16-17, 26-39).
The carnal mind therefore, is not evil. It is not the “sin nature.” It is simply ignorant. It does not have all the information about God and His true will for lives. The carnally minded person sees only externals, and bases its life and actions toward others on the external commands of religious law.
But this way of living results only in death. It is death for the person because they are not “alive” as God intended or desired, and it is death for others because living according to the law of sin leads a person to condemn and kill others in the name of God. They think this is what God wants, but it is actually the opposite.
The spiritually minded person sees the whole truth, and knows that living like God means loving like God.
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