That this is the truth may be seen in the eternal, divine idea: God is the one who as living spirit distinguishes Himself from Himself, posits another and in this other remains identical with Himself, has in this other His identity with Himself. This is the truth.
"What the doctrine of the Trinity therefore thinks, in its speculative depth, is that God is ‘not only substance, but also subject’, – not a static self-identical ‘being’ underlying all determination, but the living self-movement that generates determination from within itself and returns to itself through it, the logos that speaks itself through its own self-differentiation and returns to itself enriched by the passage. This is Hegel’s own most fundamental claim about the absolute: that the true is not only substance, but equally subject, that the absolute is not the inert ground of all things, but the living self-movement of spirit knowing itself. The Trinity is not an illustration of this claim, not a religious image that approximately captures a philosophical insight; it is the concrete content of the claim – the form in which the absolute’s own self-knowledge as subject, as living self-differentiation, as logos, first became historically available to finite spirit with the fullness and precision that the content requires. All other forms of the absolute – the God of abstract Monotheism, the Spinozistic substance, the indeterminate absolute of mysticism, the actus purus of Scholasticism – fall short of this content, because they fall short of the Trinity: they grasp one moment of the divine life – unity, or infinity, or immanence, or pure actuality – while losing the movement of self-expression that alone makes that moment true. The actus purus in particular – pure completed actuality without potentiality, the divine perfection as already fully achieved, the God who has nothing left to say because He has always already been everything He is –, as in the doctrine of aseity, is the ontotheological concept that the trinitarian doctrine, properly thought, dismantles from within: a God who is already fully actual, already completely what He is, with nothing yet to become and nowhere yet to go and no word yet to speak into the otherness of a world, is not the Father who generates the Son, not the God whose eternal life is the living pulse of self-differentiation and return, not the logos whose self-expression constitutes the ground of all things. The actus purus is the God of the understanding, the God of abstract identity, the God of mere ‘silence’; the Trinity is the God of speculative reason, the God of living self-movement, the God whose innermost nature is the eternal act of self-utterance through which He is most fully Himself.
To speak of ‘mystery’ here – to declare the Trinity beyond reason, to treat the conceptual difficulty as a mark of the doctrine’s transcendence rather than as an invitation to think more rigorously – is not reverence, but abdication; it is the understanding’s refusal to follow the logos where it leads, dressed as ‘humility’ before the divine. The Trinity does not become more truly God by being declared incomprehensible; it becomes less truly known, which is to say less truly present to the finite spirit that is called to know it. Speculative theology’s insistence on thinking the Trinity through, on following the logos in its inner necessity without shelter in mystery, is not a rationalist hubris, but fidelity, – fidelity to the content itself, which demands to be thought rather than merely venerated, which is most fully itself when it is most fully comprehended, because the Trinity is the eternal self-knowledge of the logos and a logos that stops short of its own full self-expression – that withholds itself from the thinking that would receive it – is not yet fully what it is."