According to the Greek dictionary, it means to have the nature and characteristics of the flesh (or more simply, it means “fleshly”). What, then , is the flesh? Sometimes it refers to the whole material part of man (1 Corinthians 15:39; Hebrews 5:7), and based on this meaning, carnal sometimes relates to material things like money (Romans 15:27) or to the opposite of our weapons of spiritual warfare (2 Corinthians 10:4). But the word flesh also has a metaphorical sense when it refers to our disposition to sin and to oppose or omit God in our lives. The flesh is characterized by works that include lusts and passions (Galatians 5:19-24; I John 2:16); it can enslave (Romans 7:25); and in it is nothing good (Romans 7:18). Based on this meaning of the word flesh, to be carnal means to be characterized by things that belong to the unsaved life (Ephesians 2:3).

So Great Salvation, Charles Ryrie, Victor Books, 1989, pp. 59-60.