@Putin,
"What on earth is controversial about saying causation is a temporal relationship and that all causal agents exist within the bounds of time?"
Plenty, when you use it to beg the question on a serious question. Already two serious philosophers have been cited in this thread who see causation more broadly. There are plenty more. Citing David Hume (outstanding as he is) does not close the matter. There are more kinds of causation that are discussed than just temporal causation, and you are trying to define them away.
Moving on. For reference, my definition of theistic causation:
""To say that God causes X means that there is a possible world in which X, and that God decrees the existence of such a possible world, and that it obtains; and, finally, that there is no possible world in which God does not decree the existence of such a possible world and the world still obtains."
You proceed,
"In your very definition you are invoking *time*, even though your definition isn't a definition of causation - at all. The divine decree would have to precede the "obtaining" of the universe."
No, I'm not, and no, it wouldn't. It wouldn't even make sense to speak of "preceding," would it? If you dislike the word "obtain," feel free to read "exists."
"There would at least have to be a Time A in which the decree had not yet taken place and a Time B in which the decree did take place for there to be a "beginning" of the universe or for the universe to be caused. "
On your definition, maybe, but certainly not on mine. Please remember you're trying to show an inconsistency in my views. You are not free to substitute your own definitions for mine while doing so.
You may find this definition of causation deeply dissatisfying, and you may wish to criticize it on any number of grounds (some I'm sure I'll agree with -- as I said, I've had little time to read up or be careful, and philosophical definitions are not something to throw out in 5 minutes if you can help it). But you are not free to simply insist on a definition that defines your position to be correct, and then call the Christian position inconsistent even though that is not the sense in which it is using the word. That would be fallacious.
I will suspend discussion of reverse causality until I see a semi-formalization of your argument on free will and omniscience. Entropy and the arrow of time is taking us a little far afield.
"Please spare me the suspense, what is the Christian definition of omniscience."
I confess I don't remember what I had in mind when I wrote that. I can't think of any necessary limitation from the standard definition, but for precision, we can adopt the common definition that, for any statement p, if p, then God knows p and does not believe not-p.
"Like I said, you're producing special definitions in order to make your argument work. You can call this "insulting rhetoric", but I can find no other description for what you're doing."
I wouldn't call that insulting rhretoric, for future reference -- that's just complaining about what you see as a bad argument I'm making, which is always legitimate (though it may be incorrect in a given instance). The "insulting rhetoric" remark was in reference to your requesting a definition and prepending an insult *when nothing in the argument so far had suggested that one was necessary* (and I hadn't refused to give one).
"It's not that complicated of an argument. Please explain how a timeless god can have knowledge of tensed facts - a tensed fact being a fact that is only true at a specific time - i.e. Yesterday was Saturday. It doesn't require a research paper or appeal to authority."
That's a little like saying, "Just tell me why Fermat's last theorem is true -- you don't need to cite a paper or make a big song and dance, just tell me." I exaggerate, obviously, but in truth this is a highly technical field and I'm not going to make any argument that doesn't have a stream of papers discussing it back and forth already.
That said -- God knows it the same way that you could know it. That is, suppose you go to Josh's party tonight and you see me there. You go home and crash, and then tomorrow, you check your email and find an unread message from me, dated 8 hours before the party, saying, "I'm going to Josh's party tonight." You don't have any problem evaluating the truth value of this proposition (it's true), even though it's not literally true in your own temporal context ("tonight" no longer means Monday night). The same aparatus that allows you to refer my statement to when I made it and evaluate it as true works just as well for a being that doesn't exist in time at all. To speak of knowledge in either case, you must distinguish between knowing a statement with its indexical references (such as now) fully intact, or knowing it by "dereferencing" them, i.e., by using what have been called quasi-indexical references. The key point is that refusing to acknowledge the latter undermines a vast number of ordinary human claims of knowledge, too, whereas a willingness to do so destroys the objection to the coexistence of omniscience and tensed facts. The analysis requires a subtlety in the mode of knowing a particular fact, but it is the same fact that is known.
A seminal and fairly readable short article on this is "Omniscience and Indexical Reference" by Castaneda (there's a tilde on the n). Even the basic definitions of these terms are too tediously long for me to type out here, but they are well discussed in that article's 8 pages.