The word
ousia existed in Greek culture. It occurs in the New Testament.
G3776 - οὐσία ousía, oo-see'-ah; from the feminine of ; substance, i.e. property (possessions):—goods, substance.
www.blueletterbible.org
I'm a little confused by this... you claimed they DIDN'T talk about this in the OLD Testament, then I agreed, and now you're saying they DID in the NEW Testament... what in contradiction of your previous claim? Are we just disagreeing for the sake of disagreement now? What's going on?
The angel of the Lord is an angel.
Generically true, but... more than that, I think. It appears the angel of the LORD
is the LORD but taken on the physical presence of an angel. See the story of Abraham's visitation.
The word of the Lord is God’s self-expression.
Again not wrong, but more. Virtually every prophecy of the OT starts with "the Word of the LORD came to [insert prophet's name here]." The New Testament authors read those as VISITATIONS. Not visitations by the "2nd person of the Trinity" necessarily, but it's more than just "I heard God." Those messages were hand-delivered.
The spirit of the Lord is God’s operational presence and power; personal but not another person. There is a close connection in scripture between spirit and mind.
I think I agree with this for the most part.
I don’t have a personal definition of “trinitarian”. Orthodoxy does. That is what I use.
P.S.
If I were to define “trinitarian” simply as someone who believes in the Father, the Son, and the Holy Spirit, would you accept that?
I would match that description better, but that isn't really the whole 3-in-1 concept, is it? Nearly as I can tell...
"Father" and "Son" make one coherent metaphor.
"Spirit" and "Word" make another coherent metaphor.
When you get to "Father" and "Son" and "Spirit" you have mixed your metaphors.