When we speak of the Church—allow me this parenthesis—let us think of what she truly is. Let us not have an attenuated conception of her; let us not picture to ourselves a mere spiritual administration. Let us remember that she is herself a mystery, that she is the Mystical Body of Christ, a living person, at once divine and human, whose head is Christ and all of whose members the Holy Ghost joins together, the great Contemplative who aspires to beget all men unto eternal life, and all of whose movements—so far as the Church herself is concerned (whatever the human frailty of individuals may be)—proceed from divine wisdom and the most pure gifts of grace. We shall not then bargain over the terms of our allegiance, we shall not follow her like peevish children who have to be dragged along; we shall understand that her doctrinal authority is not limited to defining solemnly what one cannot deny without being a heretic, but extends, on the contrary, according to all the degrees and all the nuances that what one calls the ordinary magisterium of the Church admits of in the tone of its voice and the authority of its affirmations, to all that concerns the integrity of faith in souls.
--Jacques Maritain, St. Thomas Aquinas, 1958