" the Church and her exegesis of revelation progress through the ever-changing periods of world history. New aspects emerge, while others wane; efforts are made to compensate for one-sided emphases, but not rarely they are simply replaced with the opposite extremes. Today too, then, it is a duty to restate the principles in a new and timely way—while being as measured as possible—and in so doing to retrieve what is of permanent value. "

― Hans Urs von Balthasar , Mary: The Church at the Source