The MysteryOfGod, the MysteryOfChrist and the MysteryHidden are all part of one mystery which has been revealed to us.
What is that revelation? -> that Jesus is Creator -> that the HolySpirit is the Father -> that we were created to be in intimate personal relationship with our Creator -> that our Creator sacrificed Himself for us -> that our Creator has cleansed us -> that we are one with our Creator by receiving His HolySpirit in Jesus name.