Ephesians 6:17

take--a different Greek word from that in Eph 6:13, Eph 6:16; translate, therefore, "receive," "accept," namely, the helmet offered by the Lord, namely, "salvation" appropriated, as Th1 5:8, "Helmet, the hope of salvation"; not an uncertain hope, but one that brings with it no shame of disappointment (Rom 5:5). It is subjoined to the shield of faith, as being its inseparable accompaniment (compare Rom 5:1, Rom 5:5). 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" (Psa 3:3; Luk 21:28). sword of the Spirit--that is, furnished by the Spirit, who inspired the writers of the word of God (Pe2 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; Rev 1:16; Rev 2:12). The two-edged sword, cutting both ways (Psa 45:3, Psa 45:5), striking some with conviction and conversion, and others with condemnation (Isa 11:4; Rev 19:15), is in the mouth of Christ (Isa 49:2), in the hand of His saints (Psa 149:6).

— Jamieson-Fausset-Brown Commentary (public domain)