@KingTut
Nothing can exist outside of existence by definition. It would be a utter logical fallacy to say, something can exist outside of time and space.
It would be an utter logical fallacy to equate space and time with existence. Modern physics has shown that both space and time are contingent and came into being at a specific point, and so they therefore cannot possibly comprise 'existence' in its entirety.
While at the same time saying it has a influence on a finite universe.
This I think is a better objection to the concept of the theistic God. It is completely contradictory that a being that is entirely atemporal should, at the same time, perform certain actions at a specific point 'in time' that affect the temporal universe.
Moreover, nothing can exist as an infinity, it would always require addition to exist, the whole point is, it is impossible to even imagine a completed infinite
Well, I think it is a logical necessity that there exists a primal, necessary 'being' or 'state' upon which all else depends for its existence. Other than that, it seems that one must assert that existence itself began, though not within 'time,' of course, and it did so for no reason, without any cause. And of course, I surely don't need to explain the absurdity of an infinite chain of causal events.
Given the necessity of a first cause, then, there must be an immutable principle upon which all else is contingent. But this need not be 'infinite' in a quantitative sense, such as existing for an infinite amount of time. Rather, it may simply be immutable and necessary for the existence of everything else.
it is impossible to even imagine a completed infinite
Well yes. A 'completed infinite' is an intrinsically incoherent concept. That and, infinity may be unimaginable, but that doesn't, of course, mean that it's impossible. There are things that human minds cannot grasp, though their existence is pretty much certain, like particular subatomic particles.
But then, I don't mean to say that I think that an actual quantitative infinite can exist, I just took issue with your seeming to imply that because it's 'impossible to imagine' that it is, therefore, impossible in the absolute sense.
Moreover Occam's Razor states that one should not multiply, beyond logical parsimony what is necessary
I know. But you're surely aware that Occam's Razor does have its limitations. There are some scenarios in which what we believe to be the most parsimonious explanation will be entirely contingent upon our limited knowledge. This seems to be one of those scenarios.
You may use it against the conceptions of the theistic God however, in that it itself is not a particularly parsimonious explanation.
I'd write more, but now, I need to sleep. Until next time.
Topic: Islame re-reads the Quran