I am clearly in over my head.
Several years ago, a leader in a local church introduced me to Open Theism. The theology appears grounded in the idea that the future is open and subject to chance and choice. God knows all there is to know about what is settled reality but can only know the future in terms of possibilities. And most of the writing I’ve encountered appears to rely on God as experiencing time. This has been explained to me as a succession of moments. Or, there is a moment (or a time) when God does not know something, and a moment (or a time) in which God does.
This has been bothering me like a bit of gravel stuck inside of a sandal. It seems to grind against the physical phenomenon of time dilation, which is an implication of Einstein’s Special Theory of Relativity (STR). STR describes what happens when velocities differ between objects in the absence of acceleration. STR is based on two things:
- The special principle of relativity: The laws of physics are the same for all observers, regardless of their velocity.
- The speed of light in a vacuum (c) is constant: That is, everyone will always measure the speed of light as being the same (i.e. c = 299,798,458 m/s), regardless of their own velocity. 
These postulates establish relationships between time, distance, velocity, and the speed of light that can be described mathematically. As regarding time this might boil down to the following. Since the speed of light is constant, as velocity increases, time slows. And if our velocities are different relative to each other, our experience of time is also different.
If I board a space ship and travel for a few years at some measurable fraction of the speed of light, when I return you will have biologically aged more rapidly than I. My “present” will be no longer aligned with yours. This time dilation can be tested in particle accelerators and with moving clocks.
And as it happens, GPS satellites factor in corrections for time dilation resulting from both velocity and gravity. Accounting for the latter requires applying Einstein’s General Theory of Relativity, and adds a level of complexity to this discussion I am simply going to avoid. The point is that the passage of time seems inseparable from the fabric of the material world. A clock does not merely measure time. Time itself is in some way part of the operation of the clock.
In an attempt to wrap my head around the matter and give it a fair hearing I am currently reading God in an open universe: science, metaphysics, and open theism.  The book has a section that discusses STR in detail. It includes a fairly dense philosophical defense of Open Theism in the context of presentism vs. eternalism, as well as tensed and tenseless ideas about time.
But all of this really seems to be beside the point as it applies to God. I am probably missing something but what I’ve read so far in the book does not seem to engage the core problem and what philosophy extrapolates from Relativity Theory might be irrelevant to this issue. Time dilation is a physical phenomenon. Which means time is an inherent feature of the material universe.
I could do with some clarification. If what is meant is that God voluntarily limits the scope of interaction with the material world there might be some common ground here. But I do not see any possible way for God to inherently experience time as a succession of moments. What would also prevent thinking of God in terms of constraints such as distance, velocity, and the speed of light? This risks anthropomorphisms like Zeus and Odin.
The bar seems quite high. A while back Stephen Hawking participated in an episode of the television show Curiosity, titled Did God Create the Universe? His answer to the question focused on the singularity of the Big Bang:
“…here too, time itself must come to a stop. You can’t get to a time before the Big Bang because there was no before the Big Bang. We have finally found something that doesn’t have a cause. Because there was no time for a cause to have existed. For me this means there is no possibility of a creator. Because there is no time for a creator to have existed.“
Hawking seems to think he has disproven God’s existence. There may be some unstated philosophical assumptions buried in the denial of causality, but let’s set that aside. What Hawking does is provide another view of how time is welded into the material order. And I think that what has actually happened is Hawking unwittingly illustrated the difficulties baked into defending any notion of anchoring God “in” time.
If my impressions of all this changes I will post an update. Perhaps there are other ways to think about this. I am neither a philosopher nor a theologian. And my understanding of physics is a bit thin. In an attempt to correct this last problem I am slowly gnawing away at a college primer on relativity theory. As I said when I started, I’m in over my head. And I’m having trouble understanding how a problematic approach to cosmology can be a good context for a theology.
 Adam Auton, An Introduction to Special Relativity (undated). Retrieved from Warp: http://adamauton.com/warp/lesson0.html. See also links at this site for further reading and a downloadable PowerPoint titled Special Relativity for Dummies.
 William Hasker, Thomas Jay Oord, and Dean Zimmerman, editors. God in an open universe: science, metaphysics, and open theism. Eugene: Pickwick Publications, 2011.
I found this book after an online back and forth with one of the editors.
 Did God Create the Universe? Curiosity, Discovery Channel, aired August 7, 2011, Darlow Smithson Productions. http://www.discovery.com/life-topics/curiosity/
 Edwin F Taylor and John Archibald Wheeler. Spacetime Physics. San Francisco: W.H Freemand and Company, 1963.
There is a second edition published in 1992. The book is listed on the Warp site above, and was also recommended in a forum as an accessible and less “mathy” introduction to modern relativity theory. I plan to acquire the more recent edition at some point. It’s a bit on the spendy side, probably as a result of being a college textbook.