John Knox (c. 1510–1572) was a Scottish clergyman, a leader of the Protestant Reformation, and a man who is considered to be the founder of the Presbyterian denomination in Scotland. Knox has been admired by contemporary theologians as someone who personified a zeal for God and a commitment to the truth of Scripture and holy living. Yet, as he grew close to death, this saint of God admitted his own personal battle with the sin nature he inherited from Adam (Romans 5:12). Knox said, “I know how hard the battle is between the flesh and the spirit under the heavy cross of affliction, when no worldly defense but present death doth appear. I know the grudging and murmuring complaints of the flesh …”
Knox’s statement sounds remarkably like that of the apostle Paul who openly acknowledged a personal struggle with his sin nature: “For we know that the Law is spiritual, but I am of flesh, sold into bondage to sin. For what I am doing, I do not understand; for I am not practicing what I would like to do, but I am doing the very thing I hate. But if I do the very thing I do not want to do, I agree with the Law, confessing that the Law is good. So now, no longer am I the one doing it, but sin which dwells in me. For I know that nothing good dwells in me, that is, in my flesh; for the willing is present in me, but the doing of the good is not. For the good that I want, I do not do, but I practice the very evil that I do not want. But if I am doing the very thing I do not want, I am no longer the one doing it, but sin which dwells in me. I find then the principle that evil is present in me, the one who wants to do good. For I joyfully concur with the law of God in the inner man, but I see a different law in the members of my body, waging war against the law of my mind and making me a prisoner of the law of sin which is in my members. Wretched man that I am! Who will set me free from the body of this death?” (Romans 7:14–24).
Paul states in his letter to the Romans that there was something “in the members” of his body that he calls “my flesh,” which produced difficulty in his Christian life and made him a prisoner of sin. Martin Luther, in his preface to the book of Romans, commented on Paul’s use of “flesh” by saying, “Thou must not understand ‘flesh,’ therefore, as though that only were ‘flesh’ which is connected with unchastity, but St. Paul uses ‘flesh’ of the whole man, body, and soul, reason, and all his faculties included, because all that is in him longs and strives after the flesh.” Luther’s comments point out that “flesh” equates to affections and desires that run contrary to God, not only in the area of sexual activity, but in every area of life.
To get a solid understanding of the term “flesh” requires examining its usage and definition in Scripture, how it manifests in the life of both believers and unbelievers, the consequences it produces, and how it can ultimately be overcome.
A Definition of the “Flesh”
The Greek word for “flesh” in the New Testament is sarx, a term that can often in Scripture refer to the physical body. However, A Greek-English Lexicon of the New Testament and Other Early Christian Literature describes the word this way: “the physical body as functioning entity; in Paul’s thought esp., all parts of the body constitute a totality known as flesh, which is dominated by sin to such a degree that wherever flesh is, all forms of sin are likewise present, and no good thing can live.”
The Bible makes it clear that humanity did not start out this way. The book of Genesis says that humankind was originally created good and perfect: “Then God said, ‘Let Us make man in Our image, according to Our likeness’ … God created man in His own image, in the image of God He created him; male and female He created them” (Genesis 1:26–27). Because God is perfect, and because an effect always represents its cause in essence [that is, a totally good God can only create good things, or as Jesus said, “A good tree cannot produce bad fruit” (Matthew 7:18)], both Adam and Eve were created good and without sin. But, when Adam and Eve sinned, their nature was corrupted, and that nature was passed along to their offspring: “When Adam had lived one hundred and thirty years, he became the father of a son in his own likeness, according to his image, and named him Seth” (Genesis 5:3, emphasis added).
The fact of the sin nature is taught in many places in Scripture, such as David’s declaration, “Behold, I was brought forth in iniquity, and in sin my mother conceived me” (Psalm 51:5). David does not mean he was the product of an adulterous affair, but that his parents passed along a sin nature to him. In theology, this is sometimes called the “Traducian” (from the Latin term meaning “from a branch”) view of human nature The Traducian view is that a person’s soul is created via his parents, with the child inheriting their fallen nature in the process.
The Bible’s view of human nature differs from that of Greek philosophy in that Scripture says the physical and spiritual nature of humankind was originally good. By contrast, philosophers such as Plato saw a dualism or dichotomy in humanity. Such thinking eventually produced a theory that the body (the physical) was bad, but a person’s spirit was good. This teaching influenced groups such as the Gnostics who believed the physical world was mistakenly created by a demi-god called the “Demiurge.” The Gnostics opposed the doctrine of Christ’s incarnation because they believed God would never take on a physical form, since the body was evil. The apostle John encountered a form of this teaching in his day and warned against it: “Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world. This is how you can recognize the Spirit of God: Every spirit that acknowledges that Jesus Christ has come in the flesh is from God, but every spirit that does not acknowledge Jesus is not from God” (1 John 4:1–3).
Further, the Gnostics taught that it did not matter what a person did in his body, since the spirit was all that mattered. This Platonic dualism had the same effect back in the first century as it does today—it leads either to asceticism or licentiousness, both of which the Bible condemns (Colossians 2:23; Jude 4).
So contrary to Greek thought, the Bible says that humanity’s nature, both the physical and spiritual, were good, yet both were adversely affected by sin. The end result of sin is a nature often referred to as the “flesh” in Scripture—something that opposes God and seeks sinful gratification. Pastor Mark Bubek defines the flesh this way: “The flesh is a built-in law of failure, making it impossible for natural man to please or serve God. It is a compulsive inner force inherited from man’s fall, which expresses itself in general and specific rebellion against God and His righteousness. The flesh can never be reformed or improved. The only hope for escape from the law of the flesh is its total execution and replacement by a new life in the Lord Jesus Christ.”
The Manifestation and Struggle with the Flesh
How does the flesh manifest itself in human beings? The Bible answers the question this way: “Now the deeds of the flesh are evident, which are: immorality, impurity, sensuality, idolatry, sorcery, enmities, strife, jealousy, outbursts of anger, disputes, dissensions, factions, envying, drunkenness, carousing, and things like these, of which I forewarn you, just as I have forewarned you, that those who practice such things will not inherit the kingdom of God” (Galatians 5:19–21).
Examples of the flesh’s outworking in the world are evident. Consider a few sad facts taken from a recent survey on the effect of pornography in America. According to the study, every second in the U.S.:
• $3,075.64 is being spent on pornography
• 28,258 Internet users are viewing pornography
• 372 Internet users are typing adult search terms into search engines
And every 39 minutes, a new pornographic video is being created in the United States. Such statistics underscore the statement made by the prophet Jeremiah who mourned that “the heart is more deceitful than all else and is desperately sick; who can understand it?” (Jeremiah 17:9).
The Consequences of the Flesh
The Bible says that living in the flesh produces a number of unfortunate consequences. First, Scripture states that those who live according to the flesh, and who never desire change or repent from their sinful behavior, will experience separation from God both in this life and the next:
• “Therefore what benefit were you then deriving from the [sinful practices] of which you are now ashamed? For the outcome of those things is death” (Romans 6:21)
• “For if you live according to the sinful nature, you will die; but if by the Spirit you put to death the misdeeds of the body, you will live” (Romans 8:13)
• “Do not be deceived, God is not mocked; for whatever a man sows, this he will also reap. For the one who sows to his own flesh will from the flesh reap corruption, but the one who sows to the Spirit will from the Spirit reap eternal life” (Galatians 6:7–8)
Further, a person also becomes a slave to his/her fleshly nature: “Do you not know that when you present yourselves to someone as slaves for obedience, you are slaves of the one whom you obey, either of sin resulting in death, or of obedience resulting in righteousness?” (Romans 6:16). This slavery always leads to a destructive lifestyle and deteriorated living. As the prophet Hosea said, “For they sow the wind and they reap the whirlwind” (Hosea 8:7).
The fact of the matter is that obeying the flesh always results in breaking God’s moral law. Nevertheless, in a very real sense, a person can never break God’s moral law, although he can certainly disobey it. For example, a person can climb up on a roof, tie a cape around his neck, and leap off the roof in hopes of breaking the law of gravity. However, he will quickly learn that he cannot fly; he cannot break the law of gravity, and the only thing he breaks in the end is himself, while proving the law of gravity in the process. The same is true of moral actions: a person may disobey God’s moral law through fleshly living, but he will only prove the moral law of God true by breaking himself in some way via his own behavior.
Overcoming the Flesh
The Bible provides a three-step process for overcoming the flesh and restoring oneself to a right relationship with God. The first step is a walk of honesty where a person acknowledges his sinful behavior before God. This involves agreeing with what the Bible says about everyone born of human parents: people are sinners and enter the world in a broken relationship with the God who made them:
• “If You, Lord, should mark iniquities, O Lord, who could stand?” (Psalm 130:3)
• “If we say that we have no sin, we are deceiving ourselves and the truth is not in us.… If we say that we have not sinned, we make Him a liar and His word is not in us” (1 John 1:8, 10)
The next step is a walk in the Spirit, which involves calling out to God for salvation and receiving His Holy Spirit that empowers a person to live rightly before God and not obey the flesh’s desires. This transformation and new walk of life is described in several places in Scripture:
• “I have been crucified with Christ; and it is no longer I who live, but Christ lives in me; and the life which I now live in the flesh I live by faith in the Son of God, who loved me and gave Himself up for me.” (Galatians 2:20)
• “Even so consider yourselves to be dead to sin, but alive to God in Christ Jesus.” (Romans 6:11)
• “But I say, walk by the Spirit, and you will not carry out the desire of the flesh.” (Galatians 5:16)
• “For all of you who were baptized into Christ have clothed yourselves with Christ.” (Galatians 3:27)
• “But put on the Lord Jesus Christ, and make no provision for the flesh in regard to its lusts.” (Romans 13:14)
• “And do not get drunk with wine, for that is dissipation, but be filled with the Spirit” (Ephesians 5:18)
• “Your word I have treasured in my heart, that I may not sin against You.” (Psalm 119:11)
The last step is a walk of death, where the flesh is starved of its desires so that it eventually dies. Even though a person is born again through the Spirit of God, he must understand he still possesses the old nature with its desires that war with the new nature and the desires that come from the Spirit. From a practical standpoint, the Christian purposely avoids feeding the old, fleshly nature and instead practices new behaviors that are driven by the Spirit:
• “But flee from [sinful actions], you man of God, and pursue righteousness, godliness, faith, love, perseverance and gentleness” (1 Timothy 6:11)
• “Now flee from youthful lusts” (2 Timothy 2:22)
• “But I discipline my body and make it my slave, so that, after I have preached to others, I myself will not be disqualified.” (1 Corinthians 9:27)
• “Therefore consider the members of your earthly body as dead to immorality, impurity, passion, evil desire, and greed, which amounts to idolatry.” (Colossians 3:5)
• “Now those who belong to Christ Jesus have crucified the flesh with its passions and desires.” (Galatians 5:24)
• “Knowing this, that our old self was crucified with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin;” (Romans 6:6)
• “But you did not learn Christ in this way, if indeed you have heard Him and have been taught in Him, just as truth is in Jesus, that, in reference to your former manner of life, you lay aside the old self, which is being corrupted in accordance with the lusts of deceit, and that you be renewed in the spirit of your mind, and put on the new self, which in the likeness of God has been created in righteousness and holiness of the truth.” (Ephesians 4:20–24)
Susanna Wesley, mother to the great preachers and hymn writers John and Charles Wesley, described sin and the flesh this way: “Whatever weakens your reasoning, impairs the tenderness of your conscience, obscures your sense of God, or takes away your relish for spiritual things, in short—if anything increases the authority and the power of the flesh over the Spirit, that to you becomes sin however good it is in itself.” One of the goals of the Christian life is the victory of the Spirit over the flesh and a change of life, which manifests in righteous living before God.
Although the struggle will be very real (which the Bible makes clear), Christians have assurance from God that He will bring them eventual success over the flesh. “For I am confident of this very thing, that He who began a good work in you will perfect it until the day of Christ Jesus” (Philippians 1:6).
 Got Questions Ministries. (2010). Got Questions? Bible Questions Answered. Bellingham, WA: Logos Bible Software.