In conversing with Trinitarians one must be extremely careful in choosing the proper words. The doctrine they embrace is so confusing(as witnessed by it’s historical origin) that a specific set of words has been designated and defined as the correct way to express the Trinity. They believe that God the Father, Jesus Christ, and the Holy Spirit are all the same being. It would be incorrect to say they think of them as “parts” of a whole, but rather 3 different expressions of the same being. It is also incorrect to say they believe that it is 3 different expressions of the same person. In this case, ‘being’ does not equal ‘person’.
We are used to naturally assuming that each man(person) is a separate being from all other persons. However when it comes to the Trinity regular use of ordinary words must be substituted for carefully crafted redefinitions. In the Trinity, God is one being in three persons. It is tantamount to suggesting that my Father who gave me life and I are obviously 2 different guys, but are only 1 being. Such a notion contradicts all rational thought.
I do not intend to provide an exhaustive treatise for why I believe this doctrine is incorrect. I will provide a summary of my thoughts on it, and provide links at the end of this post to more resources.
Trinitarians often cite passages in which Christ declares his ‘oneness’ with the Father as evidence for their being the same being. While I agree that Christ is ‘one’ with the Father, I do not agree that this is evidence for the Trinity.
John 17:21-22 is our first stop:
21That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us:
22And the glory which thou gavest me I have given them; that they may be one, even as we are one:
The simplicity of this statement is what makes it so powerful. The same relationship that exists between Christ and his disciples mirrors the relationship between Christ and his Father, at least in the aspect of unity.
Thus we see that to be ‘one’ with the Father does not demand anything further than being aligned in goals, motive, and purity.