According to the second character quality of a disciple (A regular study of God’s Word. John 8:31), we know that both a disciple and a soldier must abide in training. The military spends lots of time and money training a soldier to act with instincts in the most dangerous situations. The word of God trains a disciple to be able to discern good and evil and be equipped for every good work (2 Tim 3:16-17).
Think about the hours of training you have endured to equip you to fully perform your military duty. Think of the equipment and weapons you have been trained to operate and execute. What kind of military man or woman would you be if you did not have your equipment or your training?
God trains us and equips us to fully be and live His life in us (discipleship). He equips us for battle. The following passage is cast in military terms.
Eph. 6:10 Finally, be strong in the Lord and in the strength of His might. 11 Put on the full armor of God, so that you will be able to stand firm against the schemes of the devil. 12 For our struggle is not against flesh and blood, but against the rulers, against the powers, against the world forces of this darkness, against the spiritual forces of wickedness in the heavenly places. 13 Therefore, take up the full armor of God, so that you will be able to resist in the evil day, and having done everything, to stand firm. 14 Stand firm therefore, HAVING GIRDED YOUR LOINS WITH TRUTH, and HAVING PUT ON THE BREASTPLATE OF RIGHTEOUSNESS, 15 and having shod YOUR FEET WITH THE PREPARATION OF THE GOSPEL OF PEACE; 16 in addition to all, taking up the shield of faith with which you will be able to extinguish all the flaming arrows of the evil one. 17 And take THE HELMET OF SALVATION, and the sword of the Spirit, which is the word of God. (NASB95)
There are many comparisons we can make with this passage; however, I would like to focus on one aspect. We know we should abide in the word because God uses it to train us. But notice that it is also our weapon. It is the “sword of the Spirit.
The word of God not only trains us, but it is the weapon we use when we are in the middle of the battle. This is an important concept to think about. It trains us, and it is our weapon.
Whenever I attend military briefings made to civilians, there is always one thing that the military attributes our dominant world power to. It is not our superior weapons, technology, or numbers of troops. It is the quality of our military men and women. It is the fact that the U.S. military puts more time and money into training than any other country. Our pilots have more training flight hours, our sailors have more time at sea, and our soldiers have more time with their weapons. Not only are they trained to use their equipment, but also they are trained to make decisions that are right and just. Marines are considered Teachers and Scholars. Always learning, always teaching. Our U.S. military puts much time and money into the development of the individual military person so that they can be the best that they can be.
The greatest weapon against terrorism is a highly trained military person. So the training becomes the greatest weapon. The ability of a military person to be strong, to stand firm, and to apply the sword in battle is a result of their training.
As a disciple of Jesus, the Word of God not only trains us, but it makes us into the greatest weapon against the schemes of the devil. As you are battling for the hearts and souls of those around you, and even yourself, what are the weapons that are unbeatable? Love, humility, forgiveness, peace, trust, faith, hope, etc… God uses the Word to train us to have such unbeatable weapons. We become the weapons. We become love, forgiveness, peace, trust, faith, hope, etc…
The greatest weapon against the schemes of the devil is a fully devoted follower of Jesus. So our spiritual maturity becomes the greatest weapon. The ability of a disciple of Jesus to be strong, to stand firm, and to apply the Word of God in battle is a result of their training.
“If you abide in My word, then you are truly disciples of Mine; and you shall know the truth, and the truth shall make you free.” (John 8:31-32)
Commissioned 
Great comparison. The Word is our weapon as Christians, and the weapon is what we hope to become. In the Marine Corps, we train to get used to the interpersonal violence, training in basic martial arts, ground fighting, and answering w/ a “kill” instead of a yes. When you are out of rounds or in a close combat situation, you yourself are a weapon. As a Christian the bible is our weapon, and by training with it, aka studying, reading, spending time in the word, we can know it better and be more prepared for what the devil throws our way. I like the quote, Marines “are always teaching, always learning.”