What for John 20:28? If Jesus really was not God and all the times he said "I and the Father are one" "He who has seen the Son has seen the Father" "Before Abraham I AM!" didn't mean anything, why then did the Disciples believe he was God? Jesus then says Thomas is blessed for believing (or at least contrasts him with those who are more blessed for believing without seeing.)
John 17:21 says "Let them be one as we are one". Do you believe the Disciples are G-d too? Thus, the "I and the Father are one" (and there's only one instance of this statement, not many, unless you account for the times he says "Let them be one as we are one") comment is simply misinterpreted, and 17:21 clears it up quite nicely. It's about being one in purpose. If you don't agree, you'll have to explain John 17:21. "Let them be one AS (key word: As) we are one." This has been argued numerous times on the other Trinity threads, it's funny how commonly it's brought up as if they've never read 17:21.
Also, as I've mentioned on other threads, John 20:28 appears to be a later add-on, as the ending of John went through a series of revisions. You will see that it clashes with the ending of Matthew and Luke. If you disagree, kindly state what location the Disciples met Jesus at. The original John likely ended at 20:10 as demonstrated by Bernard Muller here:
The complete text of the original John's gospel
Again, if you disagree, kindly state where exactly the Disciples first met Jesus after the ressurection. Galilee, Jerusalem, or a Locked room in the mountains. Can't be all three. Additionally, the Doubting Thomas story would indicate that Thomas wasn't there to receive the Holy Breath.
Even if you don't mind the endings clashing and you still believe it's an authentic verse, here's one of many arguments against the very wording.
http://www.angelfire.com/space/thegospeltruth/trinity/verses/Jn20_28.html
And as for the "I AM" thing, as I mentioned earlier, the name itself "Eyheh" is actually "I shall be", and two top Trinitarian scholars from Oxford and Chicago rendered Ego Eimi as "Before Abraham I was". So on those two points, the name itself is moot. Like other arguments, this very common use of "I am" is ultimately a Modalist argument that doesn't take into account that the correct translation of the Holy name is "I shall be". It was rendered as "I shall be" in 3 Septuagints before the Sinaiticus. In addition to the actual context of what he said, which was not even himself calling himself a name but making a statement of his soul existing before Abraham. You have to really twist the grammar to get him to say he's calling himself "I am" rather than stating "I exist". Notice the word "Genesthai" for "Before Abraham was". Elsewhere, Genesthai is used as "to become", but in Greek grammar, it can be used as past tense. To stay consistent, "Ego Eimi" would be in the past tense. As Moffatt and Goodspeed and numerous others agree. This as well is argued extensively on the "Did Jesus say he was G-d" thread. See 1 John 3:8 for an example of how present tense at face value is actually intended as past tense.
http://www.scribd.com/doc/35318309/...te-readings-to-I-am-I-have-been-I-was-I-exist
As to the usage and meaning of
ego' eimi'
at John 8:58, Edwin D. Freed, Professor Emeritus of Religion, Gettysburg College, contends that “the meaning of the sentence inthe mind of the writer was: “Before Abraham was, I, the Christ, the Son of God,existed.” (“Who or what was before Abraham in John 8:58?”,
Journal for the Study of the New Testament
17, 1983, 52-59)
Dr. Beduhn also addresses this in his book.
You will also see that in John 9:9, the BLind man says "I am" (Ego Eimi) though the translations will deliberately change what he said to avoid the implications this may cause to their precious translation of John 8:58. So is the blind man claiming to be G-d too? If not, then you must drop your argument for Jesus saying "I am" as well. Jesus was declared a blasphemer not for claiming to be G-d himself but for attributing Divine qualities to himself such as living before Abraham existed, though John 1:1 and 10:33 (when the Anarthrous THeos is translated correctly) rightly state that he was "a god".
As for the name itself, "Ehyeh" does not even mean "I am" but "I shall be", and the Trinitarians are often loathe to accept this.
As for "If you've seen the Son, you've seen the Father', that's simply because he is the representative of the Father. You have to read the rest of the passage to get what Jesus was saying: "I am in the Father and the Father is in me". That does not mean "I am the Father". Though a commonly cherry picked verse for Trinitarian-proof texts, Jesus himself explains it if you actually read the entire passage.
http://examiningthetrinity.blogspot.com/2009/09/seen-me-seen-father-john-147-9.html
So as we can see, these famous examples (as well as all the others) for the Trinity are actually based on deliberate distortion of the grammar, ignoring key critical parts that explain the meaning, and outright dubious verses that are likely later interpolations. Though there are scholarly arguments on both sides, the arguments in favor of Trinitarian rendition often, if not always ignore key parts like how the words are translated elsewhere, hoping to sweep over the evidence against their positions.