We worship one God in trinity, and trinity in unity, neither confounding the persons nor dividing the substance. For the person of the Father is one; of the Son, another; of the Holy Spirit, another. But the divinity of the Father and of the Son and of the Holy Spirit is one, the glory equal, the majesty equal. Such as is the Father, such also is the Son, and such the Holy Spirit. The Father is uncreated, the Son is uncreated, the Holy Spirit is uncreated. The Father is infinite, the Son is infinite, the Holy Spirit is infinite. The Father is eternal, the Son is eternal, the Holy Spirit is eternal. And yet there are not three eternal Beings, but one eternal Being. So also there are not three uncreated Beings, nor three infinite Beings, but one uncreated and one infinite Being.

From the Athanasian Creed — 5th century

The Christian faith is centered on the triune God. The trinity, trinitas, the divine three-in-one is not an old relic of ideas believed in days past, but the essential metaphysical reality of the creator God himself. One being, one essence, eternally existent in three persons – this is our God. I had often wondered why in our leading and discipling the teaching of the doctrine of the Trinity has not taken a more central role. In my former campus ministry, we would teach new believer follow-up without a strong a focus on the Trinity. God the Father? Yes. Jesus the Son? Yes. Even, the role of the Holy Spirit, yes we teach this to new Christians. But the godhead – the Trinity is left for later days with new believers. I was a bit uncomfortable with this as the very uniqueness of the God of the Bible (as opposed to many flavors of Theism which abound) was being overlooked at times. Packer does a great job in laying out a brief statement of the Trinity:

The Son is Subject to the Father, for the Son is sent by the Father in his (the Father’s name)
The Spirit is subject to the Father, for the Spirit is sent by the Father in the Son’s name
The Spirit is subject to the Son as well as to the Father, for the Spirit is sent by the Son as well as the Father

JI Packer, Knowing God, Americanized Edition (Downers Grove: IL, Intervarsity Press, 1993) 67, 68.

The chapter closes with a discussion of the various roles and importance of the Holy Spirit. He is the source and inspiration of the New Testament – inspiring the biblical authors. He is the reason people are convicted of sin and converted to be followers of Christ. He is the source of power which accompanies the preaching of the gospel, which no human device or gimmick can mimic.

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