A Short Study of Romans 8:5-6
“For they that are after the flesh do mind the things of the flesh; but they that are after the Spirit the things of the Spirit. For to be carnally minded is death; but to be spiritually minded is life and peace.”
(Romans 8:5-6)
Paul in these God-inspired words draws a sharp contrast between believers in Christ and no condemnation (Romans 8:1) and unbelievers condemned in their sins. These two distinctions divide the whole human race in two groups, those justified in Christ (Romans 3:24) and those condemned in Adam and spiritually dead in sin (Romans 5:12). The description of the, “carnally minded” is death and eternal condemnation. They are described as those that have no faith in Christ, but rather trusting themselves that they are righteous (Luke 16:15; Luke 18:9). The carnal mind is described as those who are at, “enmity against God” (Romans 8:7), described as those who cannot satisfy the holy law of God (Romans 3:19), described as those that, “cannot please God” (Romans 8:8).
However, the description of the “spiritually minded” is much different, “to be spiritually minded is life and peace” in Christ Jesus (Colossians 1:20-21). Described as sinners, “who walk after the spirit” are those quickened together with Christ (Ephesians 2:1-6; 2nd Corinthians 5:17; 2nd Peter 1:4). They are described as those that see all of their salvation accomplished by Christ (Romans 5:8-9; 5:9-21; Romans 8:3), who have righteousness fulfilled in them by Christ, (Romans 4:6; Romans 8:4), who live by faith in Christ (Romans 3:28) and in Christ are well pleasing unto God (Ephesians 1:6; Hebrews 11:6). Those who are reconciled to God in Christ are no longer at enmity, nor against God (2nd Corinthians 5:17-21), but have submitted themselves unto God (Romans 10:3-4) and who have the Spirit of Christ dwelling in them (John 16:13-15; Romans 8:9-10; Colossians 1:27).
Now you can plainly see the vast difference between those who, “walk after the flesh” and those who, “walk after the spirit.” Now the important question of the moment is this, which way are you walking? By faith or flesh, by grace or works, mercy or merit, propitiation or pride, Christ or ceremony, truth or tradition, redemption or ritual, righteousness established by Christ or religion established by man! To walk in the flesh is death (Proverbs 14:12). To walk in the Spirit is life and peace in Christ (Romans 1:16-17). “For as many as are led by the Spirit of God, they are the sons of God.” (Romans 8:14)
T. Harding
Test All Things 
To “walk after the flesh” (Romans 8:1) or to “live after the flesh” (Romans 8:13) – both terms have the same force – is for a person to conduct himself as do all the unregenerate, who are dominated, motivated and actuated by nothing but their fallen nature. To “live after the flesh” refers not to a single act, nor even to a habit or series of acts in one direction; but rather to the whole man being governed and guided by this vile principle. That is the case with ALL who are OUT OF CHRIST: their desires, thoughts, speech and deeds all proceed from this corrupt fount. It is by the flesh that the whole of their souls are set in motion and their entire course steered. All is directed by some fleshly consideration. They act from self, or base principle; they act for self, or base end. The glory of God is nothing to them, the flesh is all in all.
(Arthur Pink)