The Holy Door of St. Peter's Basilica, reserved for the rare event, had been walled up for a quarter of a century. Just before midnight on Christmas Eve, Pope Paul VI stood before it and tapped it three times with a silver hammer. With that, workmen lowered the massive door on pulleys, chunks of broken masonry fell, and prelates washed the threshold and doorposts. After a prayer, Paul walked through the doorway into St. Peter's as cardinals, bishops, nuns, priests and lay people streamed in behind him. The Holy Year of 1975, with its theme of "renewal and reconciliation," had begun.
The...