Omniscience is the ability to know everything there is to know.
Some have questioned whether omniscience is compatible with free will; specifically, Calvinists have argued that God knows whether a person will be saved before he is born. If God has foreknowledge, then only one path (known, albeit, only to God) can be chosen and therefore allows only one action can be taken; if God had seen that the man were bound to heaven, for example, he could not be but virtuous, while were he bound to hell he must, by definition, sin.
However, some believe knowledge of what the outcome of a man or woman's free will will be does not preclude his or her freedom. They contend that it is possible for God to know how a man or woman will exercise their free will and at the same time not interfere with it. Calvinists who deny that man has free will teach that God bestows saving grace (Irresistible Grace) only on those he already knows will only by the determination of his grace choose heaven, the elect, whom he has elected to save from all eternity. Non-Calvinist Christians who assert that man has free will teach that the gift of saving grace is available to all ("not willing that any should perish") and that those who freely choose to persistently resist God's will are condemned by their own fault, and those who persistently choose to freely submit to the gift of his will to save "whosoever will" shall certainly be saved. Therefore, it is always possible to repent, to turn from evil, and choose to do good, in free-will response to the enabling power of God's saving grace.
Some believe that this creates a logical paradox, but the paradox hinges on the concept of time. That is, if God knows what a person will choose before the person makes that choice, how does the person actually have a free choice about that when the time comes? But many Christians believe that God exists outside of time, thus time does not pass for God. He is not only everywhere at once, but in all of time at once. Consequently, the time factor of the apparent paradox is removed, and the paradox disappears. That is, God does not know what the person will choose before they do so. Rather, God has always known what the person did freely choose in that person's future. Put simply, if there were to be two Omnisciences, He would be both.
This, however, raises the question in many people's minds as to why God would allow evil things, knowing that they would arise. The problem with this question is that it assumes that God would not have had some purpose in allowing evil to arise.
Some other arguments against omniscience
Philosopher Patrick Grim of SUNY Stoney Brook has argued that modern set theory disproves omniscience because there can be no single set of all truths. One way to answer this argument is by saying that God's nature transcends logic and math and therefore, as difficult as it may be to comprehend for our human minds, God is still omniscient and mathematical and logical laws do not apply to God. This somewhat similar to the defense which William of Ockham gave for the Christian doctrine of the Trinity.
- 2 Peter 3:9
- Moreland, J.P., Meister, Sweis, eds. Debating Christian Theism. Oxford: OUP, 2013. Print. Pages 169-180.