“[T]he existence of a temporal world also seems to entail intrinsic change in God in view of His knowledge of what is happening in the temporal world. For since what is happening in the world is in constant flux, so also must God’s knowledge of what is happening be in constant flux. Defenders of divine temporality have argued that a timeless God cannot know certain tensed facts about the world—for example, what is happening now—and therefore, since God is omniscient, He must be temporal…
[W]e can state, ‘In 1960 John Kennedy pledges to send a man to the moon before the end of the decade’ (the italics being a stylistic convention to show that the verb is tenseless. This sentence expresses a tenseless fact and is therefore always true… By contrast, if we replaced the tenseless verb with the past-tensed verb ‘pledged,’ then we would know that the event referred to has happened. This tensed sentence would, however, not always be true: Prior to 1960 it would be false. Prior to 1960 the tensed verb would have to be the future-tense ‘will pledge’ if the sentence is to be true. In contrast to tenseless sentences, then, tensed sentences serve to locate things in time relative to the present and so may change their truth value…
The upshot is that a being which only knew all tenseless facts about the world, including which events occur at any date and time, would still be completely in the dark about tensed facts. He would have no idea at all of what is now going on in the universe, of which events are past and which are future. On the other hand, any being which does know tensed facts cannot be timeless, for his knowledge must be in constant flux, as the tensed facts known by him change. Thus we can formulate the following argument for divine temporality:
- A temporal world exists.
- God is omniscient.
- If a temporal world exists, then if God is omniscient, God knows tensed facts.
- If God is timeless, He does not know tensed facts.
- Therefore, God is not timeless.” – Excerpts from Time and Eternity by William Lane Craig