If we have an omniscient being, then that being would presumably know about events past this point in time. Let us also assume that people that possess free will are inherently random.
This poses a problem. It is similar to the problem of having an inmoveable wall and an unstoppable object. The two simply cannot exist together. If people have free will and are random, then our being cannot know their actions, and is therefore not omniscient. If our being is omniscient, then our actions are predictable, meaning they are determined by solely outside forces and are not random. Therefore, we do not have free will.
Discuss.