Now you say we can't know? Weren't you the one that told me that God knows the end from the beginning because He is the end and the beginning? Now you want to plead ignorance because I have in fact debated it and shown you the point of doing so which is to demonstrate that the idea of timeless existence is both entirely unbiblical and totally irrational nonsense that cannot possibly be true. You want to not debate it because you have no answer and don't wish to drop your belief in Aristotle's ideas about God.There is no point debating what nobody can know. If time existed before the universe was created what was God doing all that time? There is no answer. Humans are incapable of comprehending eternity past, with or without time.
And yes, there is an answer to the question of what God was doing! God was doing whatever He wanted to be doing. The three members of the Trinity were busy having a relationship with one another that there is no doubt was dynamic, vibrant, rich and in all ways righteous, loving and holy. That might not be as specific as you'd like but that doesn't make it false and the only reason we cannot be more specific than that is because we haven't been told any specifics by those who were there. You don't know with any specificity what God was doing yesterday. Care to debate whether He was growing tomatoes out of His elbows or wouldn't you be able to concede that He was not based on nothing more than your own intuition?
As to whether we humans are capable of comprehending eternity is mostly irrelevant. The concept itself is not at all difficult to understand. Eternity is an infinite amount of time. That is to say that that's what the bible is talking about whenever the term is used. In many theological circles the term 'eternity' has been made to mean "timelessness" which, as I have already established, is incomprehensible because it is self-contradictory nonsense. So there are two senses in which we human are incapable of comprehending the idea of eternity. First, we cannot quite grasp what an infinite span of time is and secondly, the irrational cannot be comprehended, by definition. In either case, the aspects of eternity that cannot be comprehended do not undermine our ability to discuss the issue with clarity and with meaning. Nor is it so far out of our grasp that we cannot determine when we are being taught an unbiblical falsehood that aught not have any part in our doctrine, much less our theology proper (theology of God).
The bottom line is that there is a great deal that we can know about God's existence. We can know what we are taught in scripture along with that which can be deduced by means of sound reason. As such we can know that God has always existed and we can know that timeless existence is a fantasy.
Clete