As an introduction to the Trinity, this book presents the origins and development of a Trinitarian Christian culture. Gilles Emery provides the reader with the background not only to appreciate this culture, but also to enter into it. At every stage (biblical, patristic, and systematic) he pays particular attention to doxology and prayer, showing how the historical and contemplative dimensions of Trinitarian doctrine are inseparable. The mark of vibrant Trinitarian culture consists in its ability to appropriate the witness of the Scriptures to the triune God by means of the interweaving of doxological praise, creedal confession, and intellectual precision. Not...

The mystery of the Holy Trinity is “the substance of the New Testament,” Pope Leo XIII recalled in his encyclical on the Holy Spirit, Divinum illud munus (1897). The Trinity is not one topic of reflection among others, but rather it constitutes the heart of Christian faith. To affirm that the Trinity is “the substance of the New Testament” is to recognize that the Trinity is found at the center of the Gospel, that it is the essential reality of the Gospel, and that it is the very object of faith, hope, and charity. Indeed, the Holy Trinity is “the...

Faith in the Trinity rests on God’s revelation of himself in the economy of salvation. We do not have access to the Trinity outside what God revealed to us by sending his own Son and giving us his Holy Spirit. This point is crucial. Trinitarian faith is distinct from experiences that begin by observing nature, or studying cultural phenomena, or that start from arguments or human introspection. It rests exclusively on the gift that God makes when he enables believers to know him in faith. The revelation of the Trinity is accomplished by the coming of God himself into human...

In the preceding chapter, we indicated some biblical paths for entering into Trinitarian faith. It is now necessary for us to examine more closely the New Testament teaching concerning the Father, Son, and Holy Spirit. This teaching can be approached in many ways. One can consider the Gospel texts, for example, under the aspect of what they proclaim. In speaking about the Kingdom of God, they show the paternity of God and the filiation of Jesus, with whom the Holy Spirit is indissociably connected, as is particularly visible in their accounts of Jesus’ baptism. Under various titles, the writings of...

Confessions of faith in the Triune God were developed according to a variety of circumstances and occasions: the liturgy (particularly baptism), catechesis, the preaching of the faith, and the defense of the faith, as well as exorcisms and healings (because healings are an occasion to proclaim the faith). Among the functions of the formulas of faith, the principal are the teaching of the faith and the liturgy. In this chapter, we propose to examine these confessions of faith, from the New Testament up to the First Council of Constantinople in a.d. 381.

The New Testament contains various confessions of faith....

The doctrine of Trinitarian faith shared by the Catholic Church and the Orthodox Churches can be summed up by this declaration of the Second Council of Constantinople, in a.d. 553:

If anyone will not confess that the Father, Son and Holy Spirit have one nature (phusis, natura) or substance (ousia, substantia), that they have one power (dunamis, virtus) and authority (exousia, potestas), that there is a consubstantial (homoousios, consubstantialis) Trinity, one Deity to be adored in three hypostases (hupostaseis, subsistentiae) or persons (prosopa, personae): let him be anathema. For there is only one God and Father, from whom all things...

This chapter examines the Father, Son, and Holy Spirit in their distinctive properties. The divine persons are not blended: each person possesses his own personal traits. These distinct personal features constitute the “property” of each divine person: paternity and innascibility (Father), filiation (Son), and procession (Holy Spirit). The properties regard the eternal existence of the divine persons, and they allow us likewise to grasp the mode of action of these persons in creation and in salvation. We will direct our attention principally to the property of each divine person in his eternal existence, while indicating briefly the creative and salvific...

The preceding chapters have presented the doctrine of the Church on the divine persons and their properties, by explaining it with the help of St. Thomas Aquinas and other teachers. This study has undertaken to purify our understanding in order to elevate our gaze, in faith, to the mystery of God the Trinity. It is now necessary for us to return to the action of the Trinity in his work of creation, revelation, and salvation. The teaching concerning the properties of the divine persons offers a precious light for understanding more profoundly the action of these persons.

In this book,...

Without repeating the various elements that constitute this book, let us briefly survey the path traversed. Our presentation of the teaching regarding God the Trinity has comprised three steps, in an investigation guided by the quest for union with God in beatitude and eternal life.

The first step is the study of the economy in which the mystery itself is manifested and given, according to the witness of Scripture: God the Father saves humans by the salvific sending of his Son and by the sanctifying effusion of the Holy Spirit. Meditation on Scripture and on the ecclesial gift of salvation...