2 Corinthians 10:3

For though we walk in the flesh. — The phrase is generally used by St. Paul for the simple fact of bodily existence, with all its incidental infirmities and trials, but, commonly, without implying sin, as “after the flesh” does (Galatians 2:20; Philippians 1:22; 1 Timothy 3:16). The thought of participating in the sin of which the body is the occasion is, however, very close to that of sharing its weakness; and the phrase appears with this sense in Romans 8:8.

We do not war after the flesh. — Strictly, we are not carrying on our campaign. See Note on Luke 3:14, where the same word is used. As so often in St. Paul’s style, the word — especially any word like this, connected with the soldier’s life — becomes the germ of an elaborate figurative imagery, almost of a parable.