The Trinity is perhaps the most shrouded message of the Scriptures. On its surface it defies logic: How can three be one? A scrupulous search of the Bible will not yield an explicit reference. Yet Christian creeds have affirmed for centuries that God is triune and is identified as such by the Scriptures. We are tempted by the mystery of the Trinity to search for superficially satisfactory calculations, to abandon all logic in our declaration of...