One sentence, one beautiful sentence at the end of Paul’s second letter to the Corinthians (13:13) and it is clear that the notion of God has been transformed in the life and worship of the early Church:
The grace of the Lord Jesus Christ,
the love of God,
and the fellowship of the Holy Spirit be with all of you.
Ben F. Meyer wrote that the idea of the Trinity "imposed" itself on the early Church, in this case Paul, not through carefully worded dogmatic statements or philosophical treatises but through the lived reality of God in the lives of the believers. It would be centuries before the Councils of the 4th and 5th centuries could "define" the Trinitarian nature of God, but it had been experienced for centuries prior to that. It is clear when you read the Scriptures with Trinitarian eyes that you see the relationship between Father, Son and Holy Spirit, that the definition itself begins to emerge from the descriptions of God, specifically in the pages of the New Testament.
What is often lost today is the radical nature of speaking of this relationship in light of Jewish understanding of God’s Oneness. Paul, schooled as a Pharisee, would have been able to cite verse after verse from Israel’s Scripture regarding the Oneness of God, just as Jesus himself did in reciting the Shema from Deuteronomy 6:4 (see Matthew 22:37 and parr.): God is One. It was the overwhelming sense of the love of God, felt in the grace of the Lord Jesus Christ and poured out in the fellowship, the koinonia, or communion, of the Holy Spirit that lead to this transformed understanding of God. God’s Oneness was lived in three "persons" (or hypostases). This itself was realized in the life of the earliest Christians as they experienced the grace, love and communion of the living God in their midst. We need to pay attention to Paul's final phrase, which does not focus on the definition so much as the abiding presence of God in the life of the believers: may this grace, love and fellowship "be with all of you." It defines not only the reality of God, but it ought to describe also the life of the Church together.
John W. Martens
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