"Wherefore take unto you the whole armor of God, that ye may be able to withstand in the evil day, and having done all, to stand" (Ephesians 6:13).
There are many military metaphors in Scripture, but none more famous than this passage on the "armor of God." We are commanded to "put on the whole armor" so we can "stand" (be firm, well established) against "the wiles of the devil" (Ephesians 6:11). Each piece is crucial. "Truth" is first on the list (v.14).
This "girdle" (lower body armor) was designed to protect from wounds which, though not fatal, would cause extreme pain and incapacity. Truth is our protection against Satan's lie. "He is a liar" and does not live "in the truth, because there is no truth in him" (John 8:44). Satan's strength is in this untruth which he uses to "deceiveth the whole world" (Revelation 12:9). In fact, we are warned by Paul that the devil is able to disguise himself and "his ministers" as "ministers of righteousness" (II Corinthians 11:15). We can be spoiled by philosophy and other false teachings (Colossians 2:8). We can be beguiled by good-sounding words (Colossians 2:4). We can be tossed to and fro by crafty and deceptive men (Ephesians 4:14). We can even depart from the faith after listening to "seducing spirits, and doctrines of devils" (I Timothy 4:1).
Our defense against each of these potential disasters is truth. Truth is the essence of the strength of Jesus who claimed to be Truth personified (John 14:6) as He fulfilled His mission as spokesman for the Father (John 12:46-50). That "truth" is now verified by the Holy Spirit (John 16:13-15) and by the Word of God (John 17:17). We are to be doers of the Word (James 1:22), being willing to walk in the truth (III John 3), and to let our deeds be made manifest by doing truth (John 3:21). HMM III