One of the things Farrer is wrestling with in Faith and Speculation is how divine and human agency work together. How does the Infinite and the finite interact? What is the "causal joint" between the two?
We can think of two different gears in motion, God and the human mind. How, exactly, do those gears come together? When we think of the Holy Spirit helping our mental well-being, how is that happening? When God gives me peace in the midst of my anxiety is God changing the neurons in my brain? Has God's gear engaged the gears of my brain?
The trouble with this gear analogy, as Farrer points out and as we've discussed in this series, is that it tempts us to think of God's causality in creaturely terms. And when we do that, God's causality enters into a competitive relation with the world, God's gear pushing aside my gears. It's a non-zero sum dynamic, either God or me as the cause.
So we have to reject the gear metaphor, and all such metaphors of the causal joint that embed God in competitive relations with the world. As we've repeatedly pointed out in this series, God's causality is qualitatively different from creaturely causes. God differs differently.
Which brings us to one of Farrer's conclusions in Faith and Speculation. Because one part of the causal joint is Infinite the causal joint cannot be specified, not in any creaturely terms. We just don't, and won't ever, have a mechanistic picture of God's impact upon our minds and brains. This is Tanner's point that the union of the human and divine has an apophatic aspect. The causal joint is veiled in mystery. And any attempt to illuminate the causal joint is doomed to fail as our only metaphors for causality will always be creaturely metaphors, images of two gears coming together, billiard balls colliding, or dominoes falling.
Farrer's point, that the causal joint is hidden and shrouded in apophatic mystery, explains why it is difficult to describe God's relationship to our mental health as "therapeutic" or as a "coping strategy." When we conceive of therapy or coping strategies our minds are working with a creaturely framing of how therapy or a coping strategy "works" in helping us along on our mental health journey. But God, however, doesn't "work" in our mental health journey like therapy or a coping strategy.
At best, we can only observe the downstream effects of the causal joint. And those effects can be described as "therapeutic." Because of God's presence and activity in our lives we experience peace, courage, renewed hope, and strength for the day. Precisely how God brings about these effects in our lives--the causal joint--we cannot say with any psychological or neurological certainty or precision. And yet, we know the causal joint exists because when we turn to God in prayer, surrender, and dependence we feel and experience that Life which sustains and empowers us. This turn to God isn't "therapeutic" in any way that we might understand that word, but the effects of this turn upon our lives are tangible and real, the deepest foundation of our peace, wholeness and joy.
