New Testament writing once thought to have been composed by Paul in prison but more likely the work of one of Paul's disciples, who probably wrote the text sometime before AD 90 while consulting Paul's letter to the Colossians. The words “in Ephesus” are lacking in the earliest manuscripts and citations. The letter declares that the Christian mystery (gospel) of salvation, first revealed to the Apostles, is the source of true wisdom (perhaps an indirect repudiation of Gnostic claims to esoteric knowledge of the supernatural) and that salvation through Christ is offered to Jews and Gentiles alike. The writer affirms that there is but “one Lord, one faith, one baptism, one God and Father of us all” (4:5–6), who united all things in Christ, through whose death all men are redeemed. The author exhorts his readers—parents and children, masters and slaves—to lead exemplary Christian lives and to arm themselves with the “shield of faith,” “the helmet of salvation,” and “the sword of the Spirit, which is the Word of God” (6:16–17), in order to resist the wiles of the devil.