My personal belief is that the idea of a Trinity is false especially considering the fact that there is no Messianic prophecy which supports it. I have a rather neoplatonic view of this and I'll post this chart I developed so it's easier to explain:
.........................GOD (ETERNAL REALM)
...........................|
...........................| HOLY SPIRIT
.......................... |
___________________|__________________
---------------------------|
|
|...................... HUMANITY (TEMPORAL REALM)
SONS - FAITHFUL - AGNOSTIC - ATHEIST
As you can see, there is a clear separation between the temporal and eternal realm. This separation exists because, as Aristotle explains in his concept of the "Unmoved Mover", God itself could not enter the temporal realm or it would cease to be eternal, perfect, etc. and therefore cease to be God. IMO, the only thing that could remain intact in both realms would be the Holy Spirit. The Holy Spirit gives the Sons of God, prophets and the like, a revelation of God's eternal will for all things. This is what sets apart the Sons from the rest of humanity because not only are they given direct revelations of God's eternal will (Moses, Enoch, Elijah, and Jesus), but are also granted exclusive salvation, as was the case with Moses, Enoch, and Elijah, because they have a "direct connection", so to speak, with God. The Sons of God impart this exclusive knowledge onto the rest of humanity (the faithful, agnostics, and atheists) who are required to earn their salvation through a life of devotion and faith. Jesus, IMO, was not part of any Trinity, rather, he had a union with God in the sense that he shared in God's eternal will and was therefore a Son.
P.S. For those having difficulty understanding the concept of the Christian trinity think of it in terms of a human being. Human beings, from the view point of religion, are made up of three things: The Mind, The Body, and The Soul. They aren't three different beings, rather, three different components which comprise ONE being.