How can there be free will if God is all knowing?
I’ve encountered this question—or variations of it—countless times on Reddit and X. While I don’t question the sincerity of those asking the question, the comments are usually filled with people who see this question as exposing another “logical contradiction” religious people hold to for no reason other than their faith says to.
While I disagree with their stance, I understand why they believe this. It would appear that the omniscience of God implies that man does not have free will. The general argument against the compatibility between man’s free will and God’s omniscience is as follows: If God is all knowing, he infallibly knows the future. If this is the case, it means that God knows every single thing that a person will do and there is nothing a person can do to change the future God knows. Therefore, both human free will and an omniscient God cannot exist at the same time. Either everything we do is predetermined or God is not all knowing. Contrary to online critics claiming that the Christian position is based purely on “blind” faith, both faith and human reason arrive at the same conclusion that God’s omniscience is perfectly compatible with man’s free will.
Considering this from the lens of faith, Scripture reveals that God is omniscient and man has free will. God’s omniscience, his power to be all knowing, is revealed in Scripture as the Apostle John says, “for God is greater than our hearts and knows everything.” Regarding free will, there are multiple moments throughout the Bible that affirm mankind’s freedom. For instance, in the Gospel of John, Jesus implies each man has the choice to do his own will or that of God when he says “whoever chooses to do his will shall know whether my teaching is from God or whether I speak on my own.” Additionally, in the Gospel of Matthew, Jesus says that the greatest commandment is “you shall love the Lord your God with all your heart, with all your soul, and with all your mind.” This commandment would be a wasted breath if man lacks freedom—people simply would or would not love the Lord. Therefore, based on the authority of Scripture, the faith clearly states that man’s free will is compatible with God’s omniscience. While this argument may be persuasive to someone who believes in divine revelation, to many it will appear as a convenient justification for Christians to hold such a position. To meet critics where they are, Christians must explore this question using something we have in common with them: human reason.
He knows what man will do because man’s action is presently in him through his eternity.
Human reason’s inquiry into this question not only supports the truth that faith asserts but helps illuminate it more fully. To demonstrate this, we must consider man’s relationship with time versus God’s. St. Thomas Aquinas defines time as “nothing but the numbering of movement by ‘before’ and ‘after.’” This is proper to the existence of man. Man’s will acts in time and experiences existence as a linear flow of moments moving from “before” to “after.” Yet, God’s relationship with time differs greatly since he is eternal. God being eternal means there is no succession of movement, no “before” or “after,” in him. As Aquinas said, “The simultaneously whole and perfect possession of interminable life” is proper to God. It’s important to note that, according to Aquinas, this conclusion can be drawn through human reason alone. He begins his conquest to discover God’s eternity by tackling the bigger question: Does God exist? He addresses this in five ways. However, the one that will be most helpful in answering this critique is the argument from efficient cause.
The First Efficient Cause is the uncaused cause of existence in all things. This means that while all things receive their existence from him, he receives his existence from nothing outside himself. He simply is. It follows from this concept that he must also be immutable since he is existence and must therefore be pure act, having no potentiality. His immutability reveals his eternity. God must be eternal since time is a measurement of change, and it is now known that he is unchanging. This means that Aquinas is correct in his conclusion that God perfectly possesses all that is past, present, and future simultaneously whole in himself. From this understanding of God’s eternity, it naturally follows that he infallibly knows all since he experiences everything as it was, is, and will be at once. Possessing all of time at once, he knows without fault what man will do because it is happening in him at all moments. Therefore, reason leads to the conclusion that God’s omniscience does not impede or restrict man’s free will.
Although the question we started with—“How can there be free will with an all knowing God?”—appears tricky at first glance, Christians need not shy away from answering it. With the help of St. Thomas Aquinas, we find that Christians are not guilty of irrationally buying into a logical contradiction just because their faith tells them to. Instead, human reason comes to the same conclusion as faith—a result that should be no surprise to us. Man acts in time, and although God knows everything man will do before man does, it is not because he predetermined it. He knows what man will do because man’s action is presently in him through his eternity. Thus, reason arrives at the same truth that faith provides. Since God is outside of time, there are no contradictions between his omniscience and free will.
