I remember a friend asking me what I thought God was doing before the creation of the world. I answered "They were enjoying one another." He looked very quizzical and then said, "....Oh! You mean the Trinity!" I remember thinking "Well yes, what god were you thinking of?"
Yet many will think of God in ways that are divorced from the lively interaction of Father, Son and Spirit. What about you? How do you think of God's pre-creation life? His OT activity? His work in providence? His divine attributes? Do you naturally and enthusiastically conceive of these as the out-flow of the mutual relations of Persons? Is your account of these shaped by triniarian inter-play? Or do you try to conceive of these as, to all intents and purposes, unitarian activities to which we add trinitarian nuances (when we discuss salvation).
Another way of asking this is - how do you think about the relation of Oneness and Threeness in God.
Is it like this? (Forgive the very amateur graphics/formatting)
Here, Oneness is defined as the substrata - the substance of God underlying the Persons. The fundamental truths about God are cast in unitarian terms. To this is added multi-Personal considerations. Is this how you consider the interplay of Oneness and Threeness?
Or what about this view:
Here Oneness and Threeness are laid side by side. We consider 'De Deo Uno' and De Deo Trino' but separately. We can even subscribe to phrases like "the equal ultimacy of the One and the Three." Yet what we mean by this is a commitment to hold two fundamentally incommensurate doctrines of God together. It can even foster a refusal to let the Threeness of God define the Oneness. Here the One God is not constituted by the relations of the Three - Oneness is something else (divine simplicity, aseity etc etc). And the Three do not find their particular identities in the Oneness communion. No. Instead Oneness and Threeness remain unco-ordinated. It's a tri-unity by forcing One and Three together not because the 'tri' and the 'unity' mutually inform one another.
But what about if we saw things like this...
Here the Oneness is precisely the mutual relations of the particular Persons. And these particular Persons find their identity in the communion that is God's Oneness. "God's being is in His communion" (John Zizioulas). The Three are three in their Oneness (not considered apart from it). The One is one in the Threeness (not considered apart from it).
This is truly a trinity. Here the 'tri' and the 'unity' are maintained from precisely the same perspective. Here is a real 'equal ultimacy of the One and the Three.'
The benefits of such a perspective? Many - I hope to blog on many more in the fulness of time. But for now (since we're in the middle of a series on mission) - we see that our doctrine of God, whether considering 'De Deo Uno' or 'De Deo Trino' is always a doctrine of the interplay of Father, Son and Holy Spirit. It is always an investigation of the economy of salvation in which the Three are disclosed. It is always 'Gospel' theology. The God of missions is a Gospel-alone God who is served in the world by a Gospel-alone mission.