
6:17 The offensive armor included only one weapon, a short sword used in close combat. The “sword” symbolized God’s word. Because of its design, content, and origin, Scripture (the word of God) “endures forever” (1Pt 1:24–25).[1]
6:17 The “helmet of salvation” (perikephalaia, Gk.) is another extremely important piece of the Christian’s armor. The Greek word literally means “around the head”; a soldier who had lost his helmet was in danger of receiving severe head wounds which would (at the least) disorient him and render him ineffective. Similarly, a Christian who has no assurance of salvation cannot be bold in resisting Satan, in strengthening believers, or in sharing Christ with nonbelievers. The three witnesses to the believer concerning assurance are (1) the witness of the Word of God (1 John 5:13), (2) the witness of the Holy Spirit (Rom. 8:16; 1 John 5:10;), and (3) the witness of good works as a result, not a cause, of salvation (Matt. 5:16; 1 John 2:3–5). The “sword of the Spirit” (machaira, Gk.) is the only offensive weapon Paul lists. The machaira was a short, two-edged sword carried by Roman legionaries, who wielded it with deadly accuracy. This word is also used in Heb. 4:12, where the word of God is said to be “sharper than any two-edged sword.” Jesus used the Word of God defensively and offensively against Satan in Luke 4:1–13 (see Rev. 2:12). It was extremely difficult to approach a soldier well trained in the use of the machaira; the sword was short and could be moved rapidly. The fact that it was two-edged made it possible to strike on either side without changing its position in the hand, and its razor-sharp point could pierce armor. Proper use of Scripture in spiritual warfare enables the Christian to stand fast “against the wiles of the devil” (6:11).[2]
6:17 helmet of salvation. For Paul, salvation is a present experience (2:8 and note) as well as a future hope (1 Thess. 5:8). The believer’s final ground of confidence is the faithfulness of God to complete the salvation He has begun (Phil. 1:6).
sword of the Spirit, which is the word of God. The one offensive weapon in the believer’s arsenal is compared to the Roman sword, short and designed for hand-to-hand combat. See Jesus’ use of Scripture in Matt. 4:1–11; Luke 4:1–13.[3]
6:17 helmet of salvation The assurance of God’s salvation protects the believer just as a helmet protects a soldier in battle. See note on 1 Thess 5:8.
sword of the Spirit This weapon helps believers proclaim the gospel message, act on God’s behalf, and combat attacks from the devil (compare Eph 6:11–12).
word Paul’s use of the Greek word rhēma here primarily refers to the proclamation of the gospel and its ongoing work in the life of the believer (see 5:26 and note; compare Rom 10:17).[4]
6:17 the helmet of salvation. The helmet protected the head, always a major target in battle. Paul is speaking to those who are already saved, and is therefore not speaking here about attaining salvation. Rather, Satan seeks to destroy a believer’s assurance of salvation with his weapons of doubt and discouragement. This is clear from Paul’s reference to the helmet as “the hope of salvation” (Is 59:17; see note on 1Th 5:8). But although a Christian’s feelings about his salvation may be seriously damaged by Satan-inspired doubt, his salvation itself is eternally protected and he need not fear its loss. Satan wants to curse the believer with doubts, but the Christian can be strong in God’s promises of eternal salvation in Scripture (see Jn 6:37–39; 10:28, 29; Ro 5:10; 8:31–39; Php 1:6; 1Pe 1:3–5). Security is a fact; assurance is a feeling that comes to the obedient Christian (1Pe 1:3–10). the sword of the Spirit. As the sword was the soldier’s only weapon, so God’s Word is the only needed weapon, infinitely more powerful than any of Satan’s. The Gr. term refers to a small weapon (6–18 in. long). It was used both defensively to fend off Satan’s attacks, and offensively to help destroy the enemy’s strategies. It is the truth of Scripture. See notes on 2Co 10:3–5; Heb 4:12.[5]
6:17 the helmet of salvation: The intricately designed Roman helmet protected the soldier’s head and also made him look taller and more impressive. The sword of the Spirit is the only offensive weapon in the believer’s armor. This weapon is not necessarily the Bible as a whole, but the specific word that needs to be spoken in a specific situation. To have the precise word ready, a person must know the Bible intimately.[6]
6:17. The head of each Roman soldier was protected by a helmet. Paul calls the believer’s helmet, the helmet of salvation. When believers focus on what they have in Christ as a result of their salvation, this protects them from thinking that can cause them to fall. Certainty of the eternality of one’s salvation is crucial to victory in the Christian life. The three aspects of this salvation are past, present, and future. Believers have been saved from the penalty of sin and have eternal life. If believers walk in the light, they are being saved daily from the power of sin in their lives. And when Christ returns, believers will be saved even from the presence of sin.
Paul then calls on the Ephesian believers to take up the sword of the Spirit, which is the word of God. While a sword could be an offensive weapon, it was also used in defense. Since Paul’s repeated refrain was to stand (vv 11, 13, 14), this should be seen as another defensive weapon. There are a number of Greek words for sword, but this word (machaira) referred to a short two-edged sword used by Roman soldiers. The author of Hebrews used this metaphor when he said the Word of God is sharper than any two-edged sword (Heb 4:12). If believers are to stand, they must know and apply God’s Word. They are in a battle; so they must put on the full armor that God has provided for them.[7]
6:17 The helmet God provides is salvation (Isa. 59:17). No matter how hot the battle, the Christian is not daunted, since he knows that ultimate victory is sure. Assurance of eventual deliverance preserves him from retreat or surrender. “If God is for us, who can be against us?” (Rom. 8:31).
Finally, the soldier takes the sword of the Spirit, which is the word of God. The classic illustration of this is our Lord’s use of this sword in His encounter with Satan. Three times He quoted the word of God—not just random verses but the appropriate verses which the Holy Spirit gave Him for that occasion (Luke 4:1–13). The word of God here does not mean the whole Bible, but the particular portion of the Bible which best suits the occasion.
David Watson says:
God gives us all the protection that we need. We must see that there is a “ring of truth” about our walk with the Lord, that our lives are right (“righteous”) with God and with one another, that we seek to make peace wherever we go, that we lift up that shield of faith together to quench the flaming darts of the evil one, that we protect our minds from fears and anxieties that easily assail, and that we use God’s word to good effect in the power of the Spirit. Remember it was by the repeated sword thrusts of God’s word that Jesus overcame his adversary in the wilderness.[8]
6:17. The outline is divided here because the Greek word take is an imperative, rather than another participle. This parallels the imperative “stand” in verse 14. The helmet and sword are the last two pieces a soldier takes up. A helmet, being hot and uncomfortable, would be put on by a soldier only when he faced impending danger. Having one’s head guarded by a helmet gives a sense of safety, so the helmet of salvation refers either to present safety from the devil’s attacks or to a future deliverance, “the hope of salvation as a helmet” (1 Thes. 5:8).
Finally, a Roman soldier would take in hand his sword, his only offensive weapon. Of the Spirit refers to the source or origin of the sword; hence it is “the sword given by the Spirit.” “The sword of the Spirit” is specified as the Word of God. “Word” (rhēma; cf. Eph. 5:26; Rom. 10:8, 17; 1 Peter 1:25) refers to the preached Word or an utterance of God occasioned by the Holy Spirit in the heart. Believers need this “sword” to combat the enemy’s assault, much as Christ did three times when tempted by the devil (Matt. 4:1–11).[9]
17 To put on the helmet of salvation (cf. Is. 59:17), in the context of this letter, is to assure our hearts of our union with Christ—that we are already seated with him and so secure in him (cf. 2:5–8). We hold the strong ground; we are only called to ‘stand’. The final piece of armour mentioned is the sword of the Spirit, which is the word of God. This too appears to be an allusion to Is. 11:4, where the powerful word of the Messiah effects judgment (and Wisdom of Solomon 5:20 [echoing Is. 16:4–5 and 59:17] talks of ‘stern wrath’ as the Lord’s ‘sword’). Here, then, the church is given a weapon not merely of defence, but one to strike back against the powers that attack. To strike back with truth when we are personally tempted to evil; to strike back with truth when the church is attacked by false teaching; to strike back with truth when the powers seek to pervade the world around us with alien philosophies and ethical teaching; and finally to strike vigorous blows for freedom with the fearless proclamation of Christian truth such as Paul encourages in vs 19–20. But one thing above all must be remembered about this ‘weapon of offence’: the word of wrath of Is. 11:4 has become the gospel of peace, and uniting love, in Christ. And we are fighting the spiritual powers not human enemies (12). Our use of the sword of the Spirit has to reflect this, else it will become a weapon of darkness, enmity and division instead.[10]
6:17. The helmet of salvation pictures the Roman soldier’s metal protective headgear. It does not refer to our salvation in Christ. First Thessalonians speaks of the helmet of the “hope of salvation,” which is probably a parallel idea. That being the case, taking the helmet of salvation could be understood as resting our hope in the future and living in this world according to the value system of the next.
The sword of the Spirit pictures the soldier’s weapon sheathed to his belt and used both for offensive and defensive purposes. Taking the sword of the Spirit—defined for us as the Word of God—can be understood as using Scripture specifically in life’s situations to fend off attacks of the enemy and put him to flight. We see the example of Jesus using the Scripture this way in Matthew 4:1–11.[11]
6:17 “take the helmet of salvation” This is an AORIST MIDDLE (deponent) IMPERATIVE. It is symbolic of believers’ knowledge of the gospel, and their hope in Christ (cf. 1 Thess. 5:8).
© “the sword of the Spirit, which is the word of God” Paul specifically defines the believers’ offensive weapon. This was an allusion to an OT metaphor for God speaking to His people (cf. Isa. 49:2; Hosea 6:5). God’s revelation (both the living Word, Jesus Christ, and the written word, the Bible) is described in these terms in Heb. 4:12. Although a different Greek term for “word” (rhēma versus logos) is used in Hebrews, the term for “sword” is the same (the small tongue-shaped Roman weapon).
It is dangerous to draw too sharp a distinction between parallel terms in Koine Greek like “rhēma” and “logos.” This may refer to the use of the Scriptures during temptation, like Jesus’ in Matt. 4:1ff. Believers’ knowledge of the gospel will protect them in their daily spiritual struggles. This is why Scripture memorization and personal Bible study are so valuable (cf. Ps. 119:105; Prov. 6:23). This is the only offensive weapon listed among the armor. It is not only for protection, but for attack![12]
[1] Dockery, D. S. (2017). Ephesians. In E. A. Blum & T. Wax (Eds.), CSB Study Bible: Notes (p. 1879). Holman Bible Publishers.
[2] Criswell, W. A., Patterson, P., Clendenen, E. R., Akin, D. L., Chamberlin, M., Patterson, D. K., & Pogue, J., eds. (1991). Believer’s Study Bible (electronic ed., Eph 6:17). Thomas Nelson.
[3] Sproul, R. C., ed. (2005). The Reformation Study Bible: English Standard Version (p. 1715). Ligonier Ministries.
[4] Barry, J. D., Mangum, D., Brown, D. R., Heiser, M. S., Custis, M., Ritzema, E., Whitehead, M. M., Grigoni, M. R., & Bomar, D. (2012, 2016). Faithlife Study Bible (Eph 6:17). Lexham Press.
[5] MacArthur, J. F., Jr. (2006). The MacArthur study Bible: New American Standard Bible. (Eph 6:17). Thomas Nelson Publishers.
[6] Radmacher, E. D., Allen, R. B., & House, H. W. (1999). Nelson’s new illustrated Bible commentary (p. 1541). T. Nelson Publishers.
[7] Bond, J. B. (2010). The Epistle of Paul the Apostle to the Ephesians. In R. N. Wilkin (Ed.), The Grace New Testament Commentary (p. 890). Grace Evangelical Society.
[8] MacDonald, W. (1995). Believer’s Bible Commentary: Old and New Testaments (A. Farstad, Ed.; pp. 1952–1953). Thomas Nelson.
[9] Hoehner, H. W. (1985). Ephesians. In J. F. Walvoord & R. B. Zuck (Eds.), The Bible Knowledge Commentary: An Exposition of the Scriptures (Vol. 2, p. 644). Victor Books.
[10] Turner, M. (1994). Ephesians. In D. A. Carson, R. T. France, J. A. Motyer, & G. J. Wenham (Eds.), New Bible commentary: 21st century edition (4th ed., p. 1244). Inter-Varsity Press.
[11] Anders, M. (1999). Galatians-Colossians (Vol. 8, p. 191). Broadman & Holman Publishers.
[12] Utley, R. J. (1997). Paul Bound, the Gospel Unbound: Letters from Prison (Colossians, Ephesians and Philemon, then later, Philippians): Vol. Volume 8 (p. 140). Bible Lessons International.














