The shape of our face is not yet known to us.
The story of Cohle's life after the loss of his daughter is the story of sorrow and grief becoming such a burden that Cohle forgot himself and the world. Theriot challenges everyone there, including Cohle, to remember this truth. This world is a veil and we are not ourselves. The shape of our face " not yet known to us is the essence of the message. By using the term yet, Theriot indicates that the veil can be lifted, that we can know ourselves as Cohle realizes at the end of the final episode.
Cohle's insights shared with Marty mark both his enlightenment and his willingness to join the world through a real relationship with his partner. Cohle talks about descending into the darkness of death as losing my definitions. This prepares him to see the ability to join with his lost daughter as the final words of the sermon promise.
Be in him and of him and then know peace. That is his gift to us, our birthright. In the end, we will find ourselves at the beginning and will at last know ourselves and our true faces will weep in his light; and those tears, those tears will feel like a warm rain. Amen
This further elaborates Cohle's enlightenment. This is our birthright but realizing it requires profound suffering and trials, in some cases. This was one of those cases.
N.B. For those interested, a similar message appeared nearly two millennia ago:
said, "Let him who seeks continue seeking until he finds. When he
finds, he will become troubled. When he becomes troubled, he will be
astonished, and he will rule over the All." The Gospel of Thomas, Nag Hammadi Library (Trans. T.O. Lambdin)
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