What is the Doctrine of the Holy Trinity?

(CFC 234-237)

Christians are baptized “in the name of the Father and of the Son and of the Holy Spirit” Before receiving the sacrament, they respond to a three-part question when asked to confess the Father, the Son and the Spirit: “I do.” “The faith of all Christians rests on the Trinity.”

Christians are baptized in the name of the Father and of the Son and of the Holy Spirit: not in their names, for there is only one God, the almighty Father, his only Son and the Holy Spirit: the Most Holy Trinity.

The mystery of the Most Holy Trinity is the central mystery of Christian faith and life. It is the mystery of God in himself. It is therefore the source of all the other mysteries of faith, the light that enlightens them. It is the most fundamental and essential teaching in the “hierarchy of the truths of faith”.

The whole history of salvation is identical with the history of the way and the means by which the one true God, Father, Son and Holy Spirit, reveals himself to men “and reconciles and unites with himself those who turn away from sin.

The Trinity is a mystery of faith in the strict sense, one of the “mysteries that are hidden in God, which can never be known unless they are revealed by God”. To be sure, God has left traces of his Trinitarian being in his work of creation and in his Revelation throughout the Old Testament. But his inmost Being as Holy Trinity is a mystery that is inaccessible to reason alone or even to Israel’s faith before the Incarnation of God’s Son and the sending of the Holy Spirit.

The dogma of the Holy Trinity

The Trinity is One. We do not confess three Gods, but one God in three persons, the “consubstantial Trinity”. The divine persons do not share the one divinity among themselves but each of them is God whole and entire: “The Father is that which the Son is, the Son that which the Father is, the Father and the Son that which the Holy Spirit is, i.e. by nature one God.”84 In the words of the Fourth Lateran Council (1215), “Each of the persons is that supreme reality, viz., the divine substance, essence or nature.”

The divine persons are really distinct from one another. “God is one but not solitary.” “Father”, “Son”, “Holy Spirit” are not simply names designating modalities of the divine being, for they are really distinct from one another: “He is not the Father who is the Son, nor is the Son he who is the Father, nor is the Holy Spirit he who is the Father or the Son.” They are distinct from one another in their relations of origin: “It is the Father who generates, the Son who is begotten, and the Holy Spirit who proceeds.” The divine Unity is Triune.

The divine persons are relative to one another. Because it does not divide the divine unity, the real distinction of the persons from one another resides solely in the relationships which relate them to one another: “In the relational names of the persons the Father is related to the Son, the Son to the Father, and the Holy Spirit to both. While they are called three persons in view of their relations, we believe in one nature or substance.” Indeed “everything (in them) is one where there is no opposition of relationship.”90 “Because of that unity the Father is wholly in the Son and wholly in the Holy Spirit; the Son is wholly in the Father and wholly in the Holy Spirit; the Holy Spirit is wholly in the Father and wholly in the Son.”