Verse 2
grace
Grace (imparted). Ephesians 3:2-8; Ephesians 4:7,29; Romans 6:1; 2 Peter 3:18.
Verses 3–5
mystery
(See Scofield "Matthew 13:11").
Verses 6–8
That the Gentiles
That the Gentiles were to be saved was no mystery Romans 9:24-33; Romans 10:19-21. The mystery "hid in God" was the divine purpose to make of Jew and Gentile a wholly new thing--"the church, which is his Christ's body," formed by the baptism with the Holy Spirit 1 Corinthians 12:12,13 and in which the earthly distinction of Jew and Gentile disappears ; Ephesians 2:14,15; Colossians 3:10,11. The revelation of this mystery, which was foretold, but not explained by Christ Matthew 16:18 was committed to Paul. In his writings alone we find the doctrine, position, walk, and destiny of the church.
Verses 9–21
mystery
(See Scofield "Matthew 13:11").