The Catechism describes the Trinity as God's "innermost secret," which is that "God himself is an eternal exchange of love, Father, Son, and Holy Spirit ... ." The Catechism then goes on to say something mind-blowingly amazing, "... and he has destined us to share in that exchange." When this last line really hits home, it can transform our lives. We'll reflect on this powerful idea in due course, but first, let's try to appreciate the Trinity itself more deeply.