Pope Pius XI, in his encyclical Quas Primas (1925), affirmed the doctrine of the social kingship of Christ. He thereby kicked back against the tide of the modern political world with its emphasis upon religion as merely a private affair of individuals, wherein religious truth is viewed as just a subjective choice similar to one’s taste in food and drink.
Pius XI criticized this trend toward the complete privatization of the faith and emphasized that, as far as the Catholic Church is concerned, Jesus Christ is to be affirmed as the king, not just of individual souls, but of all of society, up to and including civil authority. Issued on the Feast of Christ the King (December 11th), Pope Pius wanted to remind the world that Christ is the ruler of all, and not just of the few devotees of a single “religion”.
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