Thank you, sir, that was, as always, a well-written essay. You do have a gift for focusing, amassing evidence, and presenting an argument - a gift I have fervently wanted and not (yet!) attained.
I have a few quick thoughts.
First, the scriptures are not shy about using anthropomorphisms, as you know. In a sense - and I’m just thinking out loud here - the Incarnation was an anthropomorphism, no?
Second, I don’t really understand the word ‘hypostases’, and it seems to be a term that is undefinable, unless the word ‘person’ is used as part of the definition. But if the concept ‘person’ is anthropomorphic, doesn’t the definition fail?
Third, the Son is certainly aware of the Father as being a different - what, if not Person? One does not pray to oneself, one does not mediate between oneself and man, but between God (the Father, right? It must be the Father alone, or the mediation sounds rather silly) and man.
Well, there are many unanswerable questions; the main question here is whether something that is a Mystery, and undefinable, and not able to be comprehended, can or should be normative for Christian belief. On the other hand, the NT is crystal clear about the relationship between the Father, the Son, and the Holy Spirit, and I hold to that clarity. I don’t know what else to do, frankly.
I believe that Channing was expressing his opposition to what, at his time, was current thinking. When I find some time I will try to find current (at his time) explanation of the Trinity.
Thanks again.