This passage from the New Testament book of Ephesians 6 reminds us we struggle against evil spirit powers as well as evil humans and we must don the full set of armour God provides.

Commentary from JFB follows.

EPHESIANS 6:

10 Finally, my brethren, be strong in the Lord, and in the power of his might.

11 Put on the whole armour of God, that ye may be able to stand against the wiles of the devil.

12 For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.

13 Wherefore take unto you the whole armour of God, that ye may be able to withstand in the evil day, and having done all, to stand.

14 Stand therefore, having your loins girt about with truth, and having on the breastplate of righteousness;

15 And your feet shod with the preparation of the gospel of peace;

16 Above all, taking the shield of faith, wherewith ye shall be able to quench all the fiery darts of the wicked.

17 And take the helmet of salvation, and the sword of the Spirit, which is the word of God:

18 Praying always with all prayer and supplication in the Spirit, and watching thereunto with all perseverance and supplication for all saints;

be strong—Greek, "be strengthened."

in the power of his might—Christ's might: as in Eph 1:19, it is the Father's might.

11. the whole armour—the armor of light (Ro 13:12); on the right hand and left (2Co 6:7). The panoply offensive and defensive. An image readily suggested by the Roman armory, Paul being now in Rome. Repeated emphatically, Eph 6:13. In Ro 13:14 it is, "Put ye on the Lord Jesus Christ"; in putting on Him, and the new man in Him, we put on "the whole armor of God." No opening at the head, the feet, the heart, the belly, the eye, the ear, or the tongue, is to be given to Satan. Believers have once for all overcome him; but on the ground of this fundamental victory gained over him, they are ever again to fight against and overcome him, even as they who once die with Christ have continually to mortify their members upon earth (Ro 6:2-14; Col 3:3, 5).

of God—furnished by God; not our own, else it would not stand (Ps 35:1-3). Spiritual, therefore, and mighty through God, not carnal (2Co 10:4).

wiles—literally, "schemes sought out" for deceiving (compare 2Co 11:14).

the devil—the ruling chief of the foes (Eph 6:12) organized into a kingdom of darkness (Mt 12:26), opposed to the kingdom of light.

12. Greek, "For our wrestling ('the wrestling' in which we are engaged) is not against flesh," &c. Flesh and blood foes are Satan's mere tools, the real foe lurking behind them is Satan himself, with whom our conflict is. "Wrestling" implies that it is a hand-to-hand and foot-to-foot struggle for the mastery: to wrestle successfully with Satan, we must wrestle with God in irresistible prayer like Jacob (Ge 32:24-29; Ho 12:4). Translate, "The principalities … the powers" (Eph 1:21; Col 1:16; see on Eph 3:10). The same grades of powers are specified in the case of the demons here, as in that of angels there (compare Ro 8:38; 1Co 15:24; Col 2:15). The Ephesians had practiced sorcery (Ac 19:19), so that he appropriately treats of evil spirits in addressing them. The more clearly any book of Scripture, as this, treats of the economy of the kingdom of light, the more clearly does it set forth the kingdom of darkness. Hence, nowhere does the satanic kingdom come more clearly into view than in the Gospels which treat of Christ, the true Light.

rulers of the darkness of this world—Greek, "age" or "course of the world." But the oldest manuscripts omit "of world." Translate, "Against the world rulers of this (present) darkness" (Eph 2:2; 5:8; Lu 22:53; Col 1:13). On Satan and his demons being "world rulers," compare Joh 12:31; 14:30; 16:11; Lu 4:6; 2Co 4:4; 1Jo 5:19, Greek, "lieth in the wicked one." Though they be "world rulers," they are not the ruler of the universe; and their usurped rule of the world is soon to cease, when He shall "come whose right it is" (Eze 21:27). Two cases prove Satan not to be a mere subjective fancy: (1) Christ's temptation; (2) the entrance of demons into the swine (for these are incapable of such fancies). Satan tries to parody, or imitate in a perverted way, God's working (2Co 11:13, 14). So when God became incarnate, Satan, by his demons, took forcible possession of human bodies. Thus the demoniacally possessed were not peculiarly wicked, but miserable, and so fit subjects for Jesus' pity. Paul makes no mention of demoniacal possession, so that in the time he wrote, it seems to have ceased; it probably was restricted to the period of the Lord's incarnation, and of the foundation of His Church.

spiritual wickedness—rather as Greek, "The spiritual hosts of wickedness." As three of the clauses describe the power, so this fourth, the wickedness of our spiritual foes (Mt 12:45).

in high places—Greek, "heavenly places": in Eph 2:2, "the air," see on Eph 2:2. The alteration of expression to "in heavenly places," is in order to mark the higher range of their powers than ours, they having been, up to the ascension (Re 12:5, 9, 10), dwellers "in the heavenly places" (Job 1:7), and being now in the regions of the air which are called the heavens. Moreover, pride and presumption are the sins in heavenly places to which they tempt especially, being those by which they themselves fell from heavenly places (Isa 14:12-15). But believers have naught to fear, being "blessed with all spiritual blessings in the heavenly places" (Eph 1:3).

13. take … of God—not "make," God has done that: you have only to "take up" and put it on. The Ephesians were familiar with the idea of the gods giving armor to mythical heroes: thus Paul's allusion would be appropriate.

the evil day—the day of Satan's special assaults (Eph 6:12, 16) in life and at the dying hour (compare Re 3:10). We must have our armor always on, to be ready against the evil day which may come at any moment, the war being perpetual (Ps 41:1, Margin).

done all—rather, "accomplished all things," namely, necessary to the fight, and becoming a good soldier.

14. Stand—The repetition in Eph 6:11, 14, shows that standing, that is, maintaining our ground, not yielding or fleeing, is the grand aim of the Christian soldier. Translate as Greek, "Having girt about your loins with truth," that is, with truthfulness, sincerity, a good conscience (2Co 1:12; 1Ti 1:5, 18; 3:9). Truth is the band that girds up and keeps together the flowing robes, so as that the Christian soldier may be unencumbered for action. So the Passover was eaten with the loins girt, and the shoes on the feet (Ex 12:11; compare Isa 5:27; Lu 12:35). Faithfulness (Septuagint, "truth") is the girdle of Messiah (Isa 11:5): so truth of His followers.

having on—Greek, "having put on."

breastplate of righteousness—(Isa 59:17), similarly of Messiah. "Righteousness" is here joined with "truth," as in Eph 5:9: righteousness in works, truth in words [Estius] (1Jo 3:7). Christ's righteousness inwrought in us by the Spirit. "Faith and love," that is, faith working righteousness by love, are "the breastplate" in 1Th 5:8.

15. Translate, "Having shod your feet" (referring to the sandals, or to the military shoes then used).

the preparation—rather, "the preparedness," or "readiness of," that is, arising from the "Gospel" (Ps 10:17). Preparedness to do and suffer all that God wills; readiness for march, as a Christian soldier.

gospel of peace—(compare Lu 1:79; Ro 10:15). The "peace" within forms a beautiful contrast to the raging of the outward conflict (Isa 26:3; Php 4:7).

16. Above all—rather, "Over all"; so as to cover all that has been put on before. Three integuments are specified, the breastplate, girdle, and shoes; two defenses, the helmet and shield; and two offensive weapons, the sword and the spear (prayer). Alford translates, "Besides all," as the Greek is translated, Lu 3:20. But if it meant this, it would have come last in the list (compare Col 3:14).

shield—the large oblong oval door-like shield of the Romans, four feet long by two and a half feet broad; not the small round buckler.

ye shall be able—not merely, "ye may." The shield of faith will certainly intercept, and so "quench, all the fiery darts" (an image from the ancient fire-darts, formed of cane, with tow and combustibles ignited on the head of the shaft, so as to set fire to woodwork, tents, &c.).

of the wicked—rather "of the EVIL ONE." Faith conquers him (1Pe 5:9), and his darts of temptation to wrath, lust, revenge, despair, &c. It overcomes the world (1Jo 5:4), and so the prince of the world (1Jo 5:18).

17. take—a different Greek word from that in Eph 6:13, 16; translate, therefore, "receive," "accept," namely, the helmet offered by the Lord, namely, "salvation" appropriated, as 1Th 5:8, "Helmet, the hope of salvation"; not an uncertain hope, but one that brings with it no shame of disappointment (Ro 5:5). It is subjoined to the shield of faith, as being its inseparable accompaniment (compare Ro 5:1, 5). The head of the soldier was among the principal parts to be defended, as on it the deadliest strokes might fall, and it is the head that commands the whole body. The head is the seat of the mind, which, when it has laid hold of the sure Gospel "hope" of eternal life, will not receive false doctrine, or give way to Satan's temptations to despair. God, by this hope, "lifts up the head" (Ps 3:3; Lu 21:28).

sword of the Spirit—that is, furnished by the Spirit, who inspired the writers of the word of God (2Pe 1:21). Again the Trinity is implied: the Spirit here; and Christ in "salvation" and God the Father, Eph 6:13 (compare Heb 4:12; Re 1:16; 2:12). The two-edged sword, cutting both ways (Ps 45:3, 5), striking some with conviction and conversion, and others with condemnation (Isa 11:4; Re 19:15), is in the mouth of Christ (Isa 49:2), in the hand of His saints (Ps 149:6). Christ's use of this sword in the temptation is our pattern as to how we are to wield it against Satan (Mt 4:4, 7, 10). There is no armor specified for the back, but only for the front of the body; implying that we must never turn our back to the foe (Lu 9:62); our only safety is in resisting ceaselessly (Mt 4:11; Jas 4:7).

18. always—Greek, "in every season"; implying opportunity and exigency (Col 4:2). Paul uses the very words of Jesus in Lu 21:36 (a Gospel which he quotes elsewhere, in undesigned consonance with the fact of Luke being his associate in travel, 1Co 11:23, &c.; 1Ti 5:18). Compare Lu 18:1; Ro 12:12; 1Th 5:17.

with all—that is, every kind of.

prayer—a sacred term for prayer in general.

supplication—a common term for a special kind of prayer [Harless], an imploring request. "Prayer" for obtaining blessings, "supplication" for averting evils which we fear [Grotius].

in the Spirit—to be joined with "praying." It is he in us, as the Spirit of adoption, who prays, and enables us to pray (Ro 8:15, 26; Ga 4:6; Jude 20).

watching—not sleeping (Eph 5:14; Ps 88:13; Mt 26:41). So in the temple a perpetual watch was maintained (compare Anna, Lu 2:37).

thereunto—"watching unto" (with a view to) prayer and supplication.

with—Greek, "in." Persevering constancy ("perseverance") and (that is, exhibited in) supplication are to be the element in which our watchfulness is to be exercised.

for all saints—as none is so perfect as not to need the intercessions of his fellow Christians.

The New Testament book of James, chapter 1:

12 Blessed is the man that endureth temptation: for when he is tried, he shall receive the crown of life, which the Lord hath promised to them that love him.

 13 Let no man say when he is tempted, I am tempted of God: for God cannot be tempted with evil, neither tempteth he any man:

 14 But every man is tempted, when he is drawn away of his own lust, and enticed.

 15 Then when lust hath conceived, it bringeth forth sin: and sin, when it is finished, bringeth forth death.

Commentary Critical and Explanatory on the Whole Bible

Robert Jamieson, A.R. Fausset, and David Brown, 1871

http://www.ccel.org/ccel/jamieson/jfb.xi.xx.ii.html

12. Blessed—Compare the beatitudes in the Sermon on the Mount (Mt 5:4, 10, 11).

endureth temptation—not the "falling into divers temptations" (Jas 1:2) is the matter for "joy," but the enduring of temptation "unto the end." Compare Job 5:17.

when he is tried—literally, "when he has become tested" or "approved," when he has passed through the "trying" (Jas 1:3), his "faith" having finally gained the victory.

the crown—not in allusion to the crown or garland given to winners in the games; for this, though a natural allusion for Paul in writing to the heathen, among whom such games existed, would be less appropriate for James in addressing the Jewish Christians, who regarded Gentile usages with aversion.

of life—"life" constitutes the crown, literally, the life, the only true life, the highest and eternal life. The crown implies a kingdom (Ps 21:3).

the Lord—not found in the best manuscripts and versions. The believer's heart fills up the omission, without the name needing to be mentioned. The "faithful One who promised" (Heb 10:23).

to them that love him—In 2Ti 4:8, "the crown of righteousness to them that love His appearing." Love produces patient endurance: none attest their love more than they who suffer for Him.

13. when … tempted—tried by solicitation to evil. Heretofore the "temptation" meant was that of probation by afflictions. Let no one fancy that God lays upon him an inevitable necessity of sinning. God does not send trials on you in order to make you worse, but to make you better (Jas 1:16, 17). Therefore do not sink under the pressure of evils (1Co 10:13).

of God—by agency proceeding from God. The Greek is not "tempted by," but, "from," implying indirect agency.

cannot be tempted with evil, &c.—"Neither do any of our sins tempt God to entice us to worse things, nor does He tempt any of His own accord" (literally, "of Himself"; compare the antithesis, Jas 1:18, "Of His own will He begat us" to holiness, so far is He from tempting us of His own will) [Bengel]. God is said in Ge 22:1to have "tempted Abraham"; but there the tempting meant is that of trying or proving, not that of seducement. Alford translates according to the ordinary sense of the Greek, "God is unversed in evil." But as this gives a less likely sense, English Version probably gives the true sense; for ecclesiastical Greek often uses words in new senses, as the exigencies of the new truths to be taught required.

14. Every man, when tempted, is so through being drawn away of (again here, as in Jas 1:13, the Greek for "of" expresses the actual source, rather than the agent of temptation) his own lust. The cause of sin is in ourselves. Even Satan's suggestions do not endanger us before they are made our own. Each one has his own peculiar (so the Greek) lust, arising from his own temperament and habit. Lust flows from the original birth-sin in man, inherited from Adam.

drawn away—the beginning step in temptation: drawn away from truth and virtue.

enticed—literally, "taken with a bait," as fish are. The further progress: the man allowing himself (as the Greek middle voice implies) to be enticed to evil [Bengel]. "Lust" is here personified as the harlot that allures the man.

15. The guilty union is committed by the will embracing the temptress. "Lust," the harlot, then, "brings forth sin," namely, of that kind to which the temptation inclines. Then the particular sin (so the Greek implies), "when it is completed, brings forth death," with which it was all along pregnant [Alford]. This "death" stands in striking contrast to the "crown of life" (Jas 1:12) which "patience" or endurance ends in, when it has its "perfect work" (Jas 1:4). He who will fight Satan with Satan's own weapons, must not wonder if he finds himself overmatched. Nip sin in the bud of lust.

16. Do not err in attributing to God temptation to evil; nay (as he proceeds to show), "every good," all that is good on earth, comes from God.

The extensive New Testament passage Romans chapters 3-8 gives great insight into the nature of our fight.

This can be found at http://www.biblegateway.com/passage/?search=rom3&version=KJV .

With JFB commentary starting at http://www.ccel.org/ccel/jamieson/jfb.xi.vi.iv.html .

It is MUST be noted that righteous standing with God is based on genuine faith alone in Jesus Christ.

But God wants to grow us in righteous practice too.

See, also, my pages They Came to Jesus, Wise Men Still Seek Him, Be Ready Always to Give an Answer, and my other pages.