New Testament verses relating to warfare:

Ro 13:12 The night is far spent, the day is at hand. Therefore let us cast off the works of darkness, and let us put on the armor of light.
2Co 6:7 by the word of truth, by the power of God, by the armor of righteousness on the right hand and on the left,
2Co 10:3 For though we walk in the flesh, we do not war according to the flesh.
2Co 10:4 For the weapons of our warfare are not carnal but mighty in God for pulling down strongholds,
Eph 6:11 Put on the whole armor of God, that you may be able to stand against the wiles of the devil.
Eph 6:13 Therefore take up the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand.
Eph 6:14 Stand therefore, having girded your waist with truth, having put on the breastplate of righteousness,
Eph 6:16 above all, taking the shield of faith with which you will be able to quench all the fiery darts of the wicked one.
Eph 6:17 And take the helmet of salvation, and the sword of the Spirit, which is the word of God;
Php 2:25 Yet I considered it necessary to send to you Epaphroditus, my brother, fellow worker, and fellow soldier, but your messenger and the one who ministered to my need;
1Th 5:8 But let us who are of the day be sober, putting on the breastplate of faith and love, and as a helmet the hope of salvation.
1Ti 1:18 This charge I commit to you, son Timothy, according to the prophecies previously made concerning you, that by them you may wage the good warfare,
2Ti 2:3 You therefore must endure hardship as a good soldier of Jesus Christ.
2Ti 2:4 No one engaged in warfare entangles himself with the affairs of this life, that he may please him who enlisted him as a soldier.
Phm 1:2 to the beloved Apphia, Archippus our fellow soldier, and to the church in your house:
Heb 4:12 For the word of God is living and powerful, and sharper than any two-edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart.
1Pe 2:11 Beloved, I beg you as sojourners and pilgrims, abstain from fleshly lusts which war against the soul,

(in context: Rom 13:12-Php 2:25, 1 Thess 5:8-1 Pet 2:11)