Sorry, I'm doing rational inquiry, and you're doing dogma. You can't understand my inquiry because you have no access to the evidence that supports it, and I can't accept your dogma because nobody's ever produced any evidence to support it. Speaking only
The gulf is too wide to bridge.
And by the way, "I AM!" is a phrase in English. Nobody spoke that at the time in question. So, it is a translation. And how good is the translation? Well, according to Wikipedia, not so hot, really, since there are many possible ways to render it.
I Am that I Am - Wikipedia
And for the record, even that -- in whatever language it was written in, is not something that you can attest "Who was the first to say..." The only thing you can know for certain is that it was written in a human language in a book written by humans making claims to what they could not know -- and so of course asserted was necessarily "absolute truth." From my point of view, and certainly not yours, this is a patently silly claim.