What do we mean when we say that man has free will? To address this question, we must first look at man in his totality, both body and spirit. Man exercises powers of both animals and angels. Each of these powers is naturally inclined towards a given object. For example, hearing is naturally inclined towards sound and eyesight towards light. If you clap beside someone’s ear or pass something before his eyes (assuming they are not diseased in any way), then he cannot help but hear the clap and see the thing. Our spiritual powers of knowing and willing likewise are naturally inclined towards truth and goodness. Focusing only on the will at the moment, we can say that the will is fixed towards always choosing the Good.
This is an important point to understand because it often leads to moral confusion. It is not possible for us to act contrary to the Good. Everything we choose is because we have perceived it to be good, even if we are objectively wrong. As a thought experiment, think about the person who commits suicide. Why do they do it ultimately? Because they deem it better to be dead than alive. So too with the teenage girl who cuts herself—the pain of the cut is better than feeling the interior angst. We could come up with any number of other examples, but the point is that no one can choose something they know to be bad for its own sake.
Given that we are bound by necessity to choose the Good, in what ways can we say that we have free will? We have free will with respect to individual goods. This is because each individual good merely participates in the Supreme Good itself, namely God. Thus it is lacking in some way and we are free to choose it or to choose another (albeit also limited good) in its place. But this is not the only manner in which we can exercise our free will. We can also choose the means towards those good and acts associated with them.
For example, because it is a limited good, I am free to choose to become a pianist or not. Once I decide to pursue that goal, I am free to choose what kind of piano I will buy. I am also free to choose how I will practice or even if I will practice at all.
This also helps us to understand the question as to how, if we cannot sin in heaven, we could still have free will. The idea that the will is naturally inclined to the Good means when we sin, we are actually choosing only what are apparent goods and not real goods. In Heaven because we are caught up in Goodness itself, there are no apparent goods, only real ones. Therefore, we can no longer sin.
This naturally leads us to wonder about the relationship between our free will and God. When I said that no one can force our will, this includes God Himself. This immediately presents a problem in that it seems that God is then limited. But properly understood this is not a limitation at all because He has the power to change our wills. While this seems like a mere intellectual sleight of hand, it is an important distinction for us to understand. God is always the divine pursuer and lover. He will never force Himself upon us like a rapist but will woo us like a lover.
God can change our wills in two ways. The first is to create a desire in us for some good that was not there before. The second is by introducing what St. Thomas calls a “form.” This could be something like an actual grace in which our minds our enlightened as to what is really a good for us here and now or by strengthening our wills to achieve the concrete good. In either case however it is still the person who chooses, even if he has had assistance from God in knowing and desiring.
St. Thomas offers a helpful analogy (De Veritate q.22, a.8) that makes the distinction clearer. He notes that a stone has a natural inclination (i.e. gravity) to fall to the earth. To throw it up in the air, is to violently alter its inclination. But God could also change the inclination by removing gravity so that the stone had a new inclination to go up. In that way, the stone would still be acting “freely” according to its own inclination.
With a proper understanding of free will, not as the power to do whatever I want, but the power to want what is good, comes the ability to act with authentic freedom. It helps us to see freedom not as an end itself (mere license) but as given to us for a specific purpose, moral excellence. That is why the Second Vatican Council called freedom “an exceptional sign of the divine image within man” (Gaudium et Spes, 17). God is totally free not just because He is God, but because He is Good. His laws for mankind are only blueprints for sharing in His Goodness. In this Lenten season when we atone for all of our failures of living freedom excellently, may we embrace the true freedom to live as children of God.