What does the Bible teach about carnality in the Christian life?

Carnality is temporal death - separation from fellowship with God. Every time we as Christians give in to temptation and sin, we enter temporal death. It is not a loss of salvation but a loss of fellowship. Carnality is the opposite pole from spirituality, and Scripture describes the pair in several ways: filled by means of the Spirit versus controlled by the old sin nature; in the Spirit versus in the flesh; the energy of the Spirit versus the energy of the flesh; in fellowship versus out of fellowship. The remedy is confession and correction, and the danger is delay. When we sin we can always get back on track by confession. But the longer we refuse to confess, the farther adrift we go, and the harder it becomes to turn away from the distractions and entanglements that are so attractive to the natural man. Carnality left unchecked by confession leads into the more dangerous and destructive state of spiritual retreat, or reversion. At any given moment, a believer is either one hundred percent filled by the Spirit and therefore spiritual, or not filled at all and therefore carnal (1 Cor. 3:1–4; Gal. 5:16–17; 6:1).