The mystery of the Incarnation, along with the mystery of the Trinity, sits atop the hierarchy of truth. The idea that "in Catholic doctrine there exists a 'hierarchy' of truth" is explicitly articulated in number 11 of the the Second Vatican Council's decree on ecumenism, Unitatis Redintegratio. Writing to theologians engaged in ecumenism, the Council fathers write that the truths in the hierarchy of Catholic doctrine "vary in their relation to the fundamental Christian faith". Hence, it is a deep mystery that we celebrate when we observe the nativity of a child who "For us men and for our salvation came down from heaven: by the power of the Holy Spirit was born of the Virgin Mary and became man" and who "For our sake . . was crucified under Pontius Pilate . . . suffered death and was buried."
Of course, that he was resurrected from the dead is the cornerstone of our faith. We must never lose sight of the reciprocity between Good Friday and Easter Sunday, both of which, according to theo-logic, are only made possible by God becoming man in the historical personage of Jesus of Nazareth. To make this point, with Fr.Neuhaus, we look to Pope St. Leo the Great, who in a Letter to Flavianum, wrote: