10 Finally, be strong in the Lord and in the strength of his might. 11 Put on the whole armour of God, that you may be able to stand against the schemes of the devil.12 For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places. 13 Therefore take up the whole armour of God, that you may be able to withstand in the evil day, and having done all, to stand firm. 14 Stand therefore, having fastened on the belt of truth, and having put on the breastplate of righteousness, 15 and, as shoes for your feet, having put on the readiness given by the gospel of peace. 16 In all circumstances take up the shield of faith, with which you can extinguish all the flaming darts of the evil one;17 and take the helmet of salvation, and the sword of the Spirit, which is the word of God, 18 praying at all times in the Spirit, with all prayer and supplication. To that end, keep alert with all perseverance, making supplication for all the saints."
Ephesians 6:10-18
Charles Hodge in his commentary maintains that it is not divine truth as objectively revealed, i.e. the Word of God, since that is mentioned in the next verse as 'the sword of the Spirit which is the Word of God', but rather the knowledge and belief of the truth. His point is that it is the truth of God clearly understood and cordially embraced that alone will protect the believer in 'the evil day'. This view seems to stand midway between the idea of 'truth of doctrine' and that of 'truth as integrity'. It is not clear that all these different interpretations must necessarily be alternatives, as if it must be either the one or the other, and it is questionable whether from a biblical point of view either of the opposites could ever have been thought of in isolation from the other. From the practical, spiritual point of view, we dare not exclude either the one or the other from our thinking, lest by doing so we deprive ourselves of any protection in the battle. And, of course, both belong together. In terms of 'truth of doctrine, this must mean to allow the truth of God to be a living reality in our experience, to live by it, act upon it, breath it, allow it to govern our conduct and our attitudes day by day, as a second nature. Paul speaks in Colossians 3:16 of letting the Word of Christ dwell in us richly, and this is what he surely means here. The Psalmist says (119:11), 'Thy Word have I hid in my heart, that I might not sin against Thee', and the Apostle James says (1:19-21), 'Be swift to hear ... and receive with meekness the engrafted word, which is able to save your souls' - in the hour of temptation or in any other situation. That is the girdle of truth.