mysterious and hidden wisdom: In Paul’s writings, "mystery" often means a truth that was once hidden but is now revealed in the good news about Jesus and his saving work (see Romans 11:25–27; 1 Timothy 3:9, 16).
Before time began: From the start, God wanted to save his chosen people through Jesus (see Romans 16:25–26; Ephesians 1:9–12; 3:3–12; Colossians 1:25–27) and lead them to ultimate glory in the future age (see Romans 5:2; 8:18–21, 29–30; 1 Thessalonians 2:12).