Church authority: The basis for the doctrine of the Trinity

The authority of the Church was necessary for us to know the truth of the Trinity. This most distinctively Christian doctrine of all, the one that reveals the nature of God himself, the nature of ultimate reality, was revealed by God clearly only to the Church. It was not clearly revealed to his chosen people, the Jews. It is not clearly defined in the New Testament. God waited to reveal it to the Church.

Scripture contains the data for the doctrine of the Trinity; but that is not enough, for every heretic, too, throughout history has appealed to Scripture. As a matter of historical fact, it has proved impossible for men to know the nature of the true God without the true Church. The dogmas of the Trinity and the Incarnation (and the two natures of Christ) were in fact derived from the Catholic Church.

Catholic Christianity:A Complete Catechism of Catholic Beliefs based on the Catechism of the Catholic Church by Peter Kreeft