There is probably no doctrine more difficult to explain, defend or make relevant for us mortals than the Christian doctrine of the Trinity. Christianity, a monotheistic religion which acknowledges only one God, has been accused of worshiping three Gods because of its insistence on the Trinity. The one God has three hypostasis, a Greek term that is translated into Latin as persona, and into English as person. But what does hypostasis, sometimes translated as substance, something that subsists, something that is self sustaining or self supporting, mean? Here is a working definition. Hypostasis, or substance or person is an indeterminate center of irreducible uniqueness. “Indeterminate center” means that it is non-local or as we say in Zen, “not-body and not mind”. “Center” means it both radiates out and is radiated into, or attracts into. “Irreducible uniqueness” means it cannot be boiled down to something else or substituted for or by something else. This definition or description would apply both to a human person and a divine person of the Trinity.
The Father, the Source, constantly and completely pours himself out fully into the Son, the Logos. The pouring out is so complete that from a human perspective we would say that there is nothing left of the Father to give. The Son, constantly and completely receives fully all of the Source so much so that he reflects perfectly the Source. The receiving is likewise so completely that from a human perspective we would say there is nothing left of the Son Then paradoxically the Logos constantly and completely pours himself out fully into the Source. This outpouring and inflowing is perfect selfless Love, both the Source and the Logos imitating each Other, overcoming their "Otherness" in their imitation of each other, without dissolving their Otherness.. The "catching" that Love is the Holy Spirit; the Logos "catching" it, the Source "catching" it, and we "catching" it. The Father and the Son perfectly mimic each other and that mimicry is the Holy Spirit. The mystery of the Holy Trinity is that even the One and Only God can't know himself without an Other, and can't help but love that Other completely and thus love himself completely. The over flow of that love is called creation and we humans are creation's crown meant to imitate or mirror the One God of unrelenting and unconditional Love.
Jesus, the incarnate, the enfleshed Logos, says, I do only what I see my Father doing. And again, I have come to do the Father's will. The English word "will" has come to mean "willfulness" and this is not what Jesus is saying. He is saying I desire only what the Father desires, and that desire is "seen" or revealed in the teachings, life, death and resurrection of Jesus and later in the dynamics of the teaching about the Triune God, formulated as the doctrine of the Trinity. We are what we desire. Desire gives us our sense of self, so much so that without desire we have no sense of self. Jesus desires the desire of the Father, and thus he is God's own self because his desire and the Father's desire are the same desire.
Be perfect as your heavenly Father is perfect. Love the Lord your God with all your heart, all your mind and all your soul, and love your neighbor as yourself. These are instructions to imitate the Father, to desire what the Father desires, as Jesus did. The more we do that the more we are like Jesus and as St. Paul says, children of God. In other words, our own sense of self conforms to what we desire, the divine in all its fullness. On this all of theology and doctrine depend.
Have this mind in you that was in Christ Jesus. Put on the mind of Christ. Girard says that we do not have a sense of self until we have acquired desires from others. What Paul is actually referring to is becoming Christ's own self by catching his desires, or his desire. The Church Fathers spoke of the same thing in a different way. We are made in the image of God, but we are to become the likeness of God in the course of our human life. That is, we are to have a new self created in the image of Christ, born of the acquired desire of Jesus who can now be seen as our Lord, in contrast to the lord of this world, which is the lord of mimetic rivalry, the lord of lies. The title “Lord” has lost all meaning for us today with our hyper-individualistic sense of self. But in the Mediterranean world, the “Lord” was more than the overseer and protector. He was the one to whom one looked for how to live life, what to value, how to act, who to be friends with and foes of. In short, a Lord, was the model for living successfully. Giving Jesus the title of Lord, means all those things. He is the model from whom we catching the divine desires, which are creating us anew at this moment.
We know that the whole creation has been groaning as in the pains of childbirth right up to the present time. Not only so, but we ourselves, who have the first fruits of the Spirit, groan inwardly as we wait eagerly for our adoption to sonship, the redemption of our bodies. Romans 8:22-23