Lex Orandi Lex Credenti – the Law of Prayer is the Law of Belief. This dictum is very much applicable to the doctrine of Trinity among the early Christians. It was from the worship of the early Church that this doctrine emerged.
One of the persistent features of theological development in our time is the awareness that Trinitarian theology has considerable implications for Christian worship. Worship always involves two dimensional movements, one God’s coming to the Church and the other is the Church’s response to God. Both these movements involve the action of each member of the Trinity. God calls us in a Trinitarian way to turn to Him. The Son and the Spirit as agents and mediators, who act in and through us, make divine-human communication possible. The significant point we have to consider here is that the agent who enable both God’s coming to us and our response reach to God are not less than divine persons, whose work as such is efficacious. Our God is a God who enables us to worship Him.
As a community that accepts Jesus as Lord and Saviour, we are invited to participate in Christ’s eternal worship. This worship is possible because of the work of the Holy Spirit. The Holy Spirit is the “liturgical agent” who makes possible and effects the worship of God. Christian worship no doubt is born of the outpouring of the Holy Spirit (cf. Gal 4, 6). The presence of the Holy Spirit in the Church means that worship is induced and brought into being. The Catechism of the Catholic Church affirms this role of the Holy Spirit in our prayer (CCC, 2766).
In the New Testament we have doxological statements about Jesus Christ. The purpose of these statements was to express adoration, praise, prayer, and confession in the context of cult. Christian prayers were adapted to proclaim Christ as messiah and expressed praise to God through Christ the mediator. Thus in the context of worship early Christians often gave thanks to God the Father in and through Jesus Christ. Thus Paul wrote to the Colossians: “Do everything in the name of the Lord Jesus, give thanks to God through him” (Col 3, 17).
From the form of worship they gave rise to dogmatic, ontological statements about the person of Christ and the Triune God. Indeed, there is an intimate link between the liturgy and the Christian Doctrine of God. Both are rooted in the divine economy. That means, God’s actions in the history are the basis for both the doctrine and worship of the Triune God.
Liturgy, like theology, is fundamentally an act of anamnesis, an act of rehearsing God’s actions in history: past and future, realized and promised. Christians identify their God as the powerful agent of particular actions in history. Actually, worship proceeds better by rehearsing eventful narratives of divine action. That is, through the worship of divine and personal power narrated in the Gospel story and symbolised in the Doctrine of Trinity.
The New Testament passages that clearly distinguish between the Father, the Son, and the Holy Spirit are in fact passages that formed a part of the prayer (cf. Eph 2, 17-18). The frequent use of and significance of doxologies in the liturgical worship of early Christian Communities is an indication that their worship was centred on the Blessed Trinity. From the New Testament times believers worshipped the Father, in the Spirit, through Christ the Son; and sometimes worshipped Christ directly (Mt 14, 33; 28, 9.17; Jn 9, 38), because they recognized Christ as fully God. Although the early Church also recognized the Holy Spirit as being God (Acts 5, 3-4; 2 Cor 3, 17-18), the explicit worship of the Holy Spirit appears to have developed at a later period. But although distinct as three Persons, there exists such a harmony in the Triune God that to worship one is to worship the Father, the Son, and the Holy Spirit together.