Romans 8:4-5 That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit. 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.
‘Walk not after the flesh, but after the Spirit’ by the walk of Christ in real flesh and yet without sin, He condemned sin in all flesh and made a way whereby no flesh had to continue in sin (6:1-23; 8:1-13; 2Cor. 5:17-18; 10:4-6; Gal. 5:16-26).
‘Mind’ [Greek: phroneo] set affections on. Those who set their affections on the sins of the flesh of Galatians 5:19-21; 1Corinthians 6:9-11; Colossians 3:5-10; Romans 1:29-32; Mark 7:19-21 will naturally fulfil them (Jas. 1:13-15). Those who set their affections on the things of the Spirit of Galatians 5:22-23; 1Corinthians 12:4-11; Colossians 3:12-14 will naturally fulfil them and such will not commit sin.
Many reasons are given in Romans that we should not continue living in sin: Death to sin nullifies it (6:2-3); resurrection from spiritual death (6:4-5); we walk in newness of life (6:4); death to sin and resurrection from sin means walking like Christ (6:5; 1Pet. 2:21-22; 1Jn. 2:6; 4:6, 17); the old man is crucified and dead (6:6; Eph. 4:22-24; 1Jn. 5:18); the body of sin is destroyed, that henceforth we should not sin (6:6); we are freed from sin (6:7, 18, 22); faith counts sin dead (6:8); sin has no dominion over us (6:9); sin not to reign in the body (6:12); the body must not yield to sin (6:13); married to Christ, not sin (7:4); we walk in the Spirit (8:1-4); we are made free from the law of sin (8:2); we are spiritually minded (8:6); Christ is in us, not sin (8:10); we are not debtors to sin (8:12); the Spirit mortifies sin in us (8:13); we have Spirit of freedom (8:15); intercession of Christ and the Holy Spirit keeps us (8:26-27, 34).