'Mystery of God' in the Bible

so that their hearts may be encouraged, united in love and into all the wealth of the full assurance of insight into the knowledge of the mystery of God, Christ,

And most certainly, great is the mystery of godliness: Who was revealed in the flesh, was vindicated by the Spirit, was seen by angels, was proclaimed among the Gentiles, was believed on in the world, was taken up in glory.

But in the days of the sound of the seventh angel, whenever he is about to blow the trumpet, then the mystery of God is completed, as he announced to his own slaves the prophets."