1 Corinthians 2:7

2:7 Instead we speak the wisdom of God, hidden in a mystery, that God determined before the ages for our glory.

Ephesians 1:9

1:9 He did this when he revealed to us the secret of his will, according to his good pleasure that he set forth in Christ,

Colossians 1:26-27

1:26 that is, the mystery that has been kept hidden from ages and generations, but has now been revealed to his saints. 1:27 God wanted to make known to them the glorious riches of this mystery among the Gentiles, which is Christ in you, the hope of glory.