A.T. Robertson Commentary 2 Corinthians 6:7

"in the word of truth, in the power of God; by the armor of righteousness on the right hand and on the left," — 2 Corinthians 6:7 (ASV)

On the right hand and on the left (των δεξιων κα αριστερων). Offensive weapons (οπλων) on the right, defensive on the left. See 1 Thessalonians 5:8; Ephesians 6:11 for Paul's description of the panoply of God and Ro 6:13 for the phrase "weapons of righteousness," the only kind that will stand the strain. See also Book of Wisdom 5:18ff.