Carnal Mindedness
The mind set on the flesh and the mind set on the world stand in Scripture as a single failure described from two angles. The flesh-side language belongs especially to Paul, who contrasts the mind of the flesh with the mind of the Spirit; the world-side language belongs especially to John and James, who frame love of the world as enmity with God. Behind both stands the older biblical observation that the human heart, left to itself, devises evil from its youth.
The Mind of the Flesh and the Mind of the Spirit
Paul's most direct statement of the contrast comes in Romans 8. "For the mind of the flesh is death; but the mind of the Spirit is life and peace" (Romans 8:6). The reason for the verdict follows immediately: "because the mind of the flesh is enmity against God; for it is not subject to the law of God, neither indeed can it be" (Romans 8:7). And the consequence: "and those who are in the flesh can't please God" (Romans 8:8). The chain is tight — the orientation of the mind to the flesh is enmity, and enmity with God is incapacity to please him. Earlier in the same chapter Paul has given the principle: "For those who are after the flesh mind the things of the flesh; but those who are after the Spirit the things of the Spirit" (Romans 8:5).
Galatians puts the same contrast on the language of agriculture. "For he who sows to his own flesh will of the flesh reap corruption; but he who sows to the Spirit will of the Spirit reap eternal life" (Galatians 6:8). The flesh and the Spirit are not equally productive fields; sowing to the one yields corruption, to the other eternal life. Galatians 5 frames the same opposition as a war: "For the flesh lusts against the Spirit, and the Spirit against the flesh; for these are contrary the one to the other; that you⁺ may not do the things that you⁺ want" (Galatians 5:17). The believer's freedom is not freedom for the flesh: "For you⁺, brothers, were called for freedom; only [do] not [use] your⁺ freedom for an occasion to the flesh, but through love serve as slaves to one another" (Galatians 5:13). And Romans returns to the practical command: "for if you⁺ live after the flesh, you⁺ must die; but if by the Spirit you⁺ put to death the activities of the body, you⁺ will live" (Romans 8:13).
Paul speaks of his own experience in the same vocabulary. "For I know that in me, that is, in my flesh, dwells no good thing: for to want is present with me, but to do that which is good [is] not" (Romans 7:18); "but I see a different law in my members, warring against the law of my mind, and capturing me in the law of sin which is in my members" (Romans 7:23); and the resolution: "So then I of myself with the mind, indeed, serve as a slave to the law of God; but with the flesh, to the law of sin" (Romans 7:25). The mind here is not yet the unhindered organ of obedience; the flesh contests it.
Friendship with the World as Enmity with God
James puts the same opposition in worldly rather than fleshly terms. "You⁺ adulteresses, don't you⁺ know that the friendship of the world is enmity with God? Whoever therefore would be a friend of the world makes himself an enemy of God" (James 4:4). The vocabulary of adultery binds the case to covenant infidelity: to befriend the world is to break faith with God. James 5 sketches what worldly living looks like in practice: "You⁺ have lived delicately on the earth, and taken your⁺ pleasure; you⁺ have nourished your⁺ hearts in a day of slaughter" (James 5:5).
John writes in the same register. "Don't love the world, neither the things that are in the world. If any man loves the world, the love of the Father is not in him" (1 John 2:15). The next verse anatomizes what is in the world: "For all that is in the world, the desire of the flesh and the desire of the eyes and the vainglory of life, is not of the Father, but is of the world" (1 John 2:16). The Johannine catalogue and the Pauline contrast meet here — the desires of the flesh are themselves what the world consists in.
The Pauline letters extend the warning. "in which you⁺ once walked according to the age of this world, according to the prince of the powers of the air, of the spirit that now works in the sons of disobedience" (Ephesians 2:2). "And don't be fashioned according to this age: but be transformed by the renewing of the mind, that you⁺ may prove what the will of God is — that [which is] good and acceptable and perfect" (Romans 12:2). Colossians supplies the corresponding command: "Set your⁺ mind on the things that are above, not on the things that are on the earth" (Colossians 3:2). Demas serves as a cautionary example: "for Demas forsook me, having loved this present age, and went to Thessalonica" (2 Timothy 4:10). Titus gives the converse: instruction "to the intent that, denying ungodliness and worldly desires, we should live soberly and righteously and godly in this present age" (Titus 2:12). And Paul to the Galatians: "But far be it from me to glory, except in the cross of our Lord Jesus Christ, through which the world has been crucified to me, and I to the world" (Galatians 6:14). The cross changes the relation between believer and world from friendship to mutual death.
The Carnal Mind in the Old Testament Backdrop
The Pauline contrast is built on an older biblical observation about the human heart. Genesis registers the verdict before the flood: "And Yahweh saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually" (Genesis 6:5). The verdict carries through the flood: "I will not again curse the ground anymore for man's sake, because the imagination of man's heart is evil from his youth" (Genesis 8:21). Jeremiah hears the same diagnosis in his own day: "O Jerusalem, wash your heart from wickedness, that you may be saved. How long will your evil thoughts lodge inside you?" (Jeremiah 4:14). Proverbs catalogues the failures: "A heart that devises wicked purposes, Feet that are swift in running to mischief" (Proverbs 6:18); "Evil devices are disgusting to Yahweh; But pleasant words [are] pure" (Proverbs 15:26); "The thought of foolishness is sin" (Proverbs 24:9). The Pauline doctrine of the mind of the flesh is not a New Testament invention; it is the Old Testament's verdict on human inwardness, drawn into the new contrast with life in the Spirit.
Israel's wilderness narrative supplies the paradigm case. "and the sons of Israel said to them, Oh that we had died by the hand of Yahweh in the land of Egypt, when we sat by the fleshpots, when we ate bread to the full" (Exodus 16:3); "And the mixed multitude that was among them lusted exceedingly: and the sons of Israel also wept again, and said, Who will give us flesh to eat?" (Numbers 11:4); "And they tried God in their heart By asking food according to their soul" (Psalm 78:18). The complaint at the fleshpots is precisely the mind set on the flesh. Jesus addresses the same disposition in those who follow him for the wrong reason: "You⁺ seek me, not because you⁺ saw signs, but because you⁺ ate of the loaves, and were filled" (John 6:26).
Carnal Mindedness as Death, Spiritual Mindedness as Life
The whole topic is summed up by the verse with which Paul opens the contrast in Romans 8: the mind of the flesh is death and the mind of the Spirit is life and peace (Romans 8:6). The opposite term is supplied by 1 Corinthians: "For who has known the mind of the Lord, that he should instruct him? But we have the mind of Christ" (1 Corinthians 2:16); and by Philippians: "Have this mind in you⁺, which was also in Christ Jesus" (Philippians 2:5). Carnal mindedness is what is replaced when the mind of Christ is given.
Diognetus describes the Christian's place in the world in terms that match the Pauline picture. "They are in the flesh, but do not live after the flesh" (Gr 5:8). And: "The flesh hates the soul, and without having been wronged wars against it, because the flesh is prevented from enjoying pleasures. And the world, without having been wronged, hates Christians, because they resist its pleasures" (Gr 6:5). The condition described is exactly the Romans 8 condition — life in the flesh that is no longer life after the flesh — and the world's hostility is the corresponding outward shape of friendship-with-the-world become enmity.