Christians believe that God is eternal. How is that possible we ask? If we say that God had a beginning, then we have to ask who or what created God? How was He created from nothing with infinite and absolute properties?
We could say a Being equal to Himself created God, but then who created the Being who created God? This chain of reasoning could continue as an infinite regress with no enlightenment after all our efforts to understand His origin. We are forced to concede that God either is an imaginary postulate or that God exists but had no beginning, even though that is not comprehensible to finite beings familiar with the laws of science who believe that every effect has a cause. Primitive people who believe in magic would probably find it easier than us to believe that God popped into Being at the dawn of Eternity.
The Urantia Book says that instead of envisioning universe realities as events on a linear timeline with a beginning and an end, we should envision universe realities on an ellipse with no beginning and no end. That implies that events repeat themselves, unless we conceive of the ellipse as infinite in length, so that we never return to the position on the ellipse where we entered the eternal adventure. This concept of an infinite ellipse would not only solve the problem of history repeating itself on a finite ellipse, but it also suggests that only a Being with infinite powers could comprehend fully “the great circle of Eternity” at every moment in time. In other words, God foresees the end from the beginning*, although I doubt that even a God could foresee all the individual decisions to be made by all His created children throughout the long evolution to universe destinies.
* We are speaking of a relative beginning before the Infinite I AM created the universes, and there began an outpouring of spirit beings to minister to the children of time, and a relative ending defined by The Urantia Book as the Cosmos-Infinite where God the Absolute becomes fully manifest beyond time, beyond space, and all potentials are realized as actual realities.