It's a question that has struck me as I've been looking over St Paul's Missive to the Romans and it's a question that seems to be prevalent throughout the whole Bible. Everywhere we see God engaged in an activity or undergoing a process or setting something in motion. God has apparently predestined us before the world was made, and yet can be angry with us when we chose not to do His will. This doesn't sound like an Eternal Being for whom Time itself is, although not meaningless, certainly not a constraint.
Of course, we are temporal and temporary beings whose existence and understanding of our surroundings depend on process and development. We cannot go back in time and we can only go forward faster than one second a second if we are able to harness the powers of speed as predicted by the theory of Relativity. Even then, that is just a theory and thus subject to the limitations of the scientific method. It is quite clear that a God who wishes to communicate with us allows us some freedom of metaphor and language in order to communicate some very clear facts about Himself.
The great theologians, notably St Thomas Aquinas following Boethius, will say that the Wrath of God is a metaphor for the utter rejection of Sin that stems from the Eternal and Substantial goodness of God. God is good and where good is rejected, so is God. The Old Testament God of wrathful indignation is the same God of love because wrath is a metaphor and love is a substance. To read the Old Testament seeing God as a temporal being leads many a person to reject God as a "moral monster" precisely because they cannot understand that in God there is no process - at least not one that could ever be communicated to or understood by us.
Our temporality has coloured the language of our salvation and it does mean that we have to listen very carefully to what God is saying to us.
Of course, Our Lord Jesus Christ is God who subjected Himself to temporality. To be a human being means being limited by Time and Space. Thus Our Lord in being fully human could not live forever if he was to be like us. His Death and Resurrection, however opens the transcendence of Time to those who believe in Him. We will become like Him because we are promised that we shall see Him as he really is, and we can only see Him if we are like Him.
This really does pose some difficult questions of philosophy and physics and I do not pretend that I am anywhere near finding an understanding, primarily because I don't believe that the mere human brain can ever comprehend the working of God, though I'm not quite sure what "ever" means in this context.
Romans viii.30: "Moreover whom he did predestinate , them he also called : and whom he called , them he also justified : and whom he justified , them he also glorified ." We are indeed justified by faith, and glorified because we are justified. Thus in calling us, God gives us Faith in that call. The events we have presented here to us are meant to be understood that way. God has spoken through St Paul and this is what we are to understand. Predestination causes calling which causes justification which causes glorification. However, that is a very temporal way of looking at things. I've used the word "cause" here deliberately, and want to understand that word "cause" as St Thomas Aquinas would want, to wit "cause" means "reason why"
The Greek verbs (predestine, called, justified, glorified) in the Aorist tense indicating a single action in its entirety, and St Paul shows us how each action of God depends on another and yet God doesn't have that dependence on Time. When does that predestination take place? Relativity tells us that it is possible for events to be simultaneous in one time-frame but one preceding the other in another. This lack of temporality doesn't affect the chain of "reason why",
So how are we to understand this? Well, we listen to St Paul, we are glorified because we are justified because we are called because we are predestined. Were we predestined in Time? No, because God predestined us "before the world began". As St Paul says to St Timothy:
We were given grace before the world began. Of course this is not entirely meaningful if by "world" we mean the Universe including Time. God created Time as well: we know that because God created all things visible and invisible. Thus, the causes of our salvation and glorification are not within Time, but are within God alone.
We know God because God presents Himself to us in our lifetimes by giving us the unwrapped present called Faith. We can choose to open it or not. If we do so, then we begin a journey of journeying in justification, glorification, redemption and salvation which we may abort at any time.
God sees our lives all at once from birth to death. He sees all our intentions and desires from birth to death, all our actions from birth to death. He does not control us, but knows us in the present tense of His Eternity, not in the chronologically causal network of Time. We are predestined in our entirety, chosen by God for salvation in our entirety, and that includes our free-will which is part of our substance as a human being. It is meaningless to say that the elect have already been chosen because that implies a temporal event and the choice is made by God from His Eternity. He wills all of us to be saved, but chooses those who choose to be saved, and chooses them from the present of Eternity. If we are predestined from eternity, then we are called from eternity, justified from eternity and glorified from eternity. The chain of causation is a chain from eternity.
This is a fascinating subject that I pray God will give me the time, inclination and understanding to explore. Even if we don't understand fully the mechanics of our salvation, we know that each of us can be saved by belief in God - actively holding, developing, and feeding the faith that God gives us to find Him. For then, we shall be called, justified, glorified, sanctified and caught up in His Eternity which we may only see darkly through the glass of our minds, but then face to face.