What defines this consensus, above all—what distinguishes orthodoxy from heresy, the central river from the delta—is a commitment to mystery and paradox. Mysteries abide at the heart of every religious faith, but the Christian tradition is uniquely comfortable preaching dogmas that can seem like riddles, offering answers that swiftly lead to further questions, and confronting believers with the possibility that the truth about God passes all our understanding.
Thus orthodox Christians insist that Jesus Christ was divine and human all at once,
that the Absolute is somehow Three as well as One,
that God is omnipotent and omniscient and yet nonetheless leaves us free to choose between good and evil.
They propose that the world is corrupted by original sin and yet somehow also essentially good, with the stamp of its Creator visible on every star and sinew.
They assert that the God of the Old Testament, jealous and punitive, is somehow identical to the New Testament’s God of love and mercy.
They claim that this same God sets impossible moral standards and yet forgives every sin.
They insist that faith alone will save us, yet faith without works is dead.
And they propose a vision of holiness that finds room in God’s Kingdom for all the extremes of human life—fecund families and single-minded celibates, politicians and monastics, queens as well as beggars, soldiers and pacifists alike…
… But if this spirit of paradox and mystery, of both/and rather than either/or, has made Christianity extraordinarily adaptable, it has exposed the faith to a constant stream of criticism as well. One man’s mystery is another man’s incoherence, and the paradoxes of Christian doctrine have always been a source of scandal as well as strength—not only among atheists, but also among the many honest believers to whom orthodox Christian doctrine looks like a hopeless muddle or else transparent sophistry…
…The great Christian heresies vary wildly in their theological substance, but almost all have in common a desire to resolve Christianity’s contradictions, untie its knotty paradoxes, and produce a cleaner and more coherent faith.