Let us learn from Paul, who explains who those “girded” ones are. Hear what he himself says: “Therefore, let your loins be girded with truth.” You see, therefore, that Paul knew the girded ones, those who were encircled by the belt of truth. So truth also ought to be our belt, if we have preserved the sacrament of this army and belt. For if truth is the belt by which we are girded for the army of Christ, then whenever we speak a falsehood and a lie proceeds from our mouth, we are ungirded from the army of Christ and loosened from the belt of truth. Therefore, if we are in the truth, we are girded; but if in the false, ungirded. Instead let us imitate those “forty thousand girded men proceeding to the war in the sight of the Lord,” and let us always be girded with truth.
To be sure, it is not enough for you in the sight of people to seem to preserve the truth. For certainly it is possible to deceive humans and to seem truthful. But in doing so you are not girded about “with truth,” unless also “in the sight of the Lord” you have preserved truth, that is, not only the things people hear from your voice but also the things God examines in your heart. Let nothing false be on the tongue; let nothing counterfeit be in the heart, as the prophet says about such things, “Those who speak peace with their neighbor but have evil in their hearts.” Therefore the one who wishes to be “girded in the sight of the Lord” and to proceed to capture Jericho ought to be apart from all these things, because when we cross over the Jordan River, we cross over to battles and wars.
[AD 253] Origen of Alexandria on Joshua 4:12-13