Ephesians 6:14 Stand firm then, with the belt of truth buckled around your waist...
We are moving into the Full Armor of God, and here Paul begins by talking about the belt of truth buckled around our waists.
Jesus reminds his disciples in John 14 that He is the way, the truth, and the life, and in a world that is full of relativism and subjectivity, we've lost what objective truth is. It's not an idea or something that *we* can define but is Christ Himself!
So often, when we're wrestling with powers and principalities in our own strength, we convince ourselves of falsehoods and untruths, but the Holy Spirit is the one that guides us unto all truth! Whenever we're trying to stand firm in the Lord, we must remember to stand firm in the Truth of God's Presence.