When Paul concludes his letter to the Christians in Ephesus and refers to the various pieces of the armor of God one would think he had previously, in that letter, explained to them of what this armor consists. And he does:
The Helmet of Salvation
2:8For by grace are ye saved through faith;
The Shield of Faith
2:8 and that (faith) not of yourselves: it is the gift of God:
9Not of works, lest any man should boast.
The Breast Plate of Righteousness
2:10 For we are his workmanship, created in Christ Jesus unto good works, which God hath before ordained that we should walk in them.
Shoes of the Gospel of Peace
1:2 Grace be to you, and peace, from God our Father, and from the Lord Jesus Christ.
The Sword of the Spirit
1:13In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise,
The Belt of Truth
4:20But ye have not so learned Christ;
21If so be that ye have heard him, and have been taught by him, as the truth is in Jesus: