High Quality Content by WIKIPEDIA articles! The theology of Pope Pius XII comprised forty-one encyclicals, and almost 1000 messages, and speeches during his long pontificate. The encyclicals Mystici Corporis and Mediator Dei clarified membership and participation in the Church. The encyclical Divino Afflante Spiritu opened the doors for biblical research. But his magisterium was far larger and is difficult to summarize. In numerous speeches Catholic teaching is related to various aspects of life, education, medicine, politics, war and peace, the life of saints, Mary, the mother of God, things eternal and contemporary.