Life in the Trinity: God's threeness and oneness

This post continues a series in the book Life in the Trinity by Donald Fairbairn. For other posts in the series, click a number: 1345678.

In chapter 3, Fairbairn addresses differing views of the Trinity. He notes that, "the Western church has emphasized the oneness of God..."  whereas, "the Eastern church has stressed God's threeness." Why the difference?  Because, "whether one starts with the one or the three depends on how one interprets the flow of biblical revelation about the Trinity" (p39).

The Old Testament emphasizes God's oneness (e.g. Isaiah 43-45 and Deuteronomy 6:4-9). Then the New Testament testifies to this one God's threeness (the Father is God, the Son is God, and the Holy Spirit is God). Both ideas are true and essential, but a problem arises when they are reduced to a mechanistic formula. Instead, the Bible speaks of God's oneness and threeness in a relational context - God is revealed as personal being who is both one and three.

In this relational context, God is one in that he is unique. This is stressed in the Old Testament because the immediate audience viewed God in the context of the culture's dominant polytheism. Israel needed first to understand that there is but one God, and his name is Yahweh, the Great I-Am; their God.

Though the Old Testament hints that this one God is plural (God, Word/Wisdom, Spirit), it remains for Jesus (and his apostles in the New Testament) to reveal that the one God of Israel is tri-personal. Fairbairn comments:
God [with 'God' in the NT typically referring to the Father] has a Son, and a Spirit, and...these two are persons (thus they can have relationship with the Father and each other) and also that they are not separate gods but are united to the Father and each other so as to be a single God....The New Testament writers do not use the word God to refer in the abstract to God's essence or substance [as though God were a mere concept], nor do they treat the Father, Son and Spirit as some kind of subdivisions within God. Instead, the New Testament uses the word God primarily to refer to the Father, and on the basis of this usage, it affirms that the Son and Spirit are God as well, and indeed are the same God as the Father. (p43)
As scriptural examples, Fairbairn cites 1Corinthians 8:5-62Corinthians 13:14, Galatians 4:4-6 and Ephesians 4:4-6, then concludes:
The biblical idea is not so much that there is one divine essence in which Father, Son and Spirit participate. Rather it is that there is one God, the Father, but there are also two other persons who are equal to him and united to him and each other in such a way that they are one being, one God. (p44)
Fairbairn notes that, in his view, this is "precisely the way the early church understood God" (p44). He also notes that the early church as a whole began in their understanding of God with God's threeness - and that with a relational emphasis. The shift to a more mechanistic focus on God's oneness, was primarily a later, and unfortunate, Western Development (see pp44-45).

Concerning the more relational understanding of God, with an emphasis on God's threeness, Fairbairn cites the Nicene Creed. This ancient creed identifies the one God as the Father and then concentrates on showing the equality of the Son and the Spirit to the Father:
The working understanding of the Trinity in this creed is that there are three persons who are equal and who therefore are a single God. The Son and Spirit are identified with the Father  even as they are acknowledged to be distinct persons. (pp 48-49)
Fairbairn then shows that the New Testament revelation (particularly in the Upper Room discourse of John 13-17), is that from all eternity, the Father has loved the Son and has been "in" the Son. He continues:
One cannot speak of love and relationship unless one is speaking of distinct persons, so the distinctions between the persons are indicative of who God has always been... So instead of thinking in terms of One, who is somehow also Three, we need to think in terms of Three, who have always been in relationship one to another and who are united in such a way that they are a single God rather than three separate gods. I have argued that this is the way the New Testament itself describes God, and it was one of the most fundamental things the church fathers recognized about the biblical witness. (p49)