[count-your-change]

John 10:30 (I and the Father are one)is often cited as a support for the trinity doctrine but the question is, HOW are they one?

Jesus prayed at John 17:20-22 that his followers would one just as he and the Father were one, that they would be in union with him and he in union with the Father.
So How are we to understand John 10:30? As part of a trinitarian formula? No, rather that Jesus and his father acted and spoke as one, in unison of thought and purpose just as he prayed for his followers to be one.

In fact Jesus says at John 14:28 that his father is greater than he.

[Cronos]

Good points -- reading through just John 17:20-22, John 10:30 is probably the basis of the thought that we are all of God or the basis of those who believe that there are no separate "persons" in th Godhead.

[Iscool]

Mar 13:19 For in those days shall be affliction, such as was not from the beginning of the creation which God created unto this time, neither shall be.

Eph 3:9 And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ:

God created everything...Jesus created everything...

It was revealed by the God to the Apostles who revealed it to us hundreds of years before the Catholic church could figure it out, or accept it...

God never said to understand it...He would just like us to believe it...

So I don't understand it, but I believe it...I don't understand all that I know...

[Mad Dawg]

In fact Jesus says at John 14:28 that his father is greater than he.

From the so-called Athanasian Creed:

33. Equal to the Father as touching His Godhead, and inferior to the Father as touching His manhood.

I do not post this to say that it's right, but merely to say that Trinitarian theology thinks it has dal with the "The Father is greater than I," saying.