Catholic Culture Liturgical Living
Catholic Culture Liturgical Living

Does Prayer Change God's Mind?

by David Arias


David Arias briefly explores St. Thomas Aquinas' explanation of how efficacious prayer works within God's unchanging Providence. St. Thomas provides the answer for contemporary process theologians, who often contradict Church teaching on this matter. Arias also seeks to reconcile man's free will with the power of prayer to effect a certain outcome. The answer lies in a richer understanding of Providence and causation.

Larger Work

Homiletic & Pastoral Review


24 - 26 & 28 - 29

Publisher & Date

Ignatius Press, San Francisco, CA, November 2003

Is there a place for genuinely efficacious prayer in God's unchangeable providence? Many think not. That is, one can find many today who think that the nature of efficacious prayer and the nature of God's unchangeable providence are utterly incompatible with each other. "Process philosophers" (i.e., philosophers who argue that God cannot be totally unchangeable, omnipotent, etc.) such as Charles Hartshorne and Lewis Ford are first amongst those who hold to this incompatibility thesis.1 But why would one hold to such a position? Why would one deny that efficacious prayer can coexist with God's unchangeable providence?

Before examining the sort of argument which process philosophers are wont to present in favor of their position, it behooves us to define our terms. What precisely is meant by "efficacious prayer" and by God's "unchangeable providence"?

To begin, prayer is commonly called efficacious (or effective) when, in response to a petition made in prayer, God brings about some effect in the created order which in some way answers the prayer. For example, if a man prays that his mother be healed of cancer and, in response to his prayer, God actually heals the man's mother of cancer, then the man's prayer would be said to be efficacious. That prayer can be efficacious is clearly attested both in Scripture and in official Church documents.2

Now, Catholic doctrine also unwaveringly affirms the fact that God's providence is absolutely unchangeable in every way.3 St. Thomas Aquinas provides us with a clear picture of what is meant when we speak of God's "providence." He says, "Since God is the Cause of things through His intellect [together with His will], and since it must be that the exemplar of every one of His effects pre-exists in Him, it is necessary that the exemplar of the order of things to their end pre-exist in the divine mind. This exemplar of things ordered to their end is, properly speaking, providence."4 St. Thomas additionally makes the point that everything, insofar as it is, is immediately subject to God's providence.5 This, of course, includes all free human acts performed by human beings. Also, since God's providence is one with the divine essence, which is absolutely unchangeable in every respect, it follows that God's providence must itself be unchangeable in every respect.

From these notions of efficacious prayer and God's unchangeable providence, then, process philosophers like Hartshorne and Ford formulate their argument against Catholic doctrine. They say that if prayer is efficacious, then it must be the case that our prayers really matter to God. God must really "listen" to our prayers in a genuine sense. If we are to affirm the efficacy of prayer, as in the case of the man whose mother had cancer, then it must be that the man's prayer in a true sense helped to bring about the divinely caused effect of his mother's recovery. If this man had not prayed, then presumably his mother would not have been healed, or at least she would not have been healed as a response to his prayer. So far what the process philosophers say sounds pretty good. But, they then go on to argue that such a conception of efficacious prayer is wholly incompatible with the unchangeableness of God's providence. What they have in mind is something like this: If God's providence is unchangeable, then whatever God has willed to bring about in the created order is going to come about no matter what any creature does about it. As a result, if God wills from all eternity to heal the man's mother of cancer, then whether the man prays or not his mother will in fact be healed from cancer, as God has foreordained. On the other hand, if God wills from all eternity not to heal the man's mother of cancer, then whether the man prays or not his mother will not in fact be healed from cancer, as God has foreordained. As a result, it seems that to affirm the unchangeability of God's providence is to deny the efficacy of prayer. That is, to say that God's providence is unchangeable seems to imply that petitionary prayer is a superfluous and unnecessary act, which has no effect whatsoever. Process philosophers themselves view this objection against Catholic doctrine as decisive and insurmountable. As a result, they wind up rejecting the doctrine concerning God's unchangeable providence in an attempt to maintain the doctrine of the efficacy of prayer.

So what is the proper Catholic response to this argument? First, we should recognize that any argument against our Holy Faith (insofar as it contradicts the truths which God has supernaturally revealed) is necessarily one, which fails to demonstrate its conclusion. St. Thomas Aquinas gives us the reason for this: "Since faith rests upon infallible truth, and since it is impossible for what is contrary to truth to be demonstrated, it is evident that the arguments which are brought against faith are not demonstrations but rather are arguments which can be answered."6 One can find essentially the same principle taught in the first Vatican Council's decree on faith and reason.7 Now, after recognizing that all such arguments against the Catholic Faith are in principle answerable, we should then, according to our abilities, proceed to offer such an answer or refutation.

It's interesting that none other than St. Thomas Aquinas offers a sound theological answer to the argument of the process philosophers. Moreover, this answer was given by St. Thomas some seven hundred years before Hartshorne or Ford ever penned their arguments against Catholic doctrine. Let's take a look at what the Angelic Doctor has to say on these matters.

One place in his writings where St. Thomas addresses the topic at hand is in his well-known Summa Theologiae. In the second part of the second part of this work, St. Thomas asks whether or not it is becoming to pray (utrum sit conveniens orare).8 In laying out his own position on this matter, the Angelic Doctor reviews three ancient erroneous positions regarding the efficacy (or lack thereof) of prayer. Some of the ancients, St. Thomas says, held that human matters are not governed whatsoever by divine providence. As a result, they maintained that it is wholly unnecessary and in fact superfluous to pray to God at all. St. Thomas says that the prophet Malachi refers to those who maintained this position when he writes: "You have said: 'It is vain to serve God'" (Malachi 3:14). Presumably, those who held to this position did so because they found it intellectually difficult to accept that their human acts could be truly free while, at the same time, governed by divine providence. So, it seems that in an attempt to resolve their difficulty, the adherents of this first position affirmed the existence of free human acts while they denied that these same acts were subject to God's providence.

In addition to this position, some other ancients held that it is altogether worthless to pray, owing to the fact (as they maintained) that all things, including human matters, come about of necessity. That is, these ancients denied the existence of any contingent causes or free causes in the world. As St. Thomas notes, some of those amongst this second group of ancients held to this deterministic position precisely because they acknowledged the absolute immutability of God's providence. In other words, some amongst this second group of ancients failed to see how human freedom and the efficacy of prayer could co-exist with the immutability of God's providence. As a consequence, they opted to uphold the latter by denying the former. What these first two erroneous positions on prayer have in common is precisely the view that, in the end, prayer is necessarily inefficacious and useless. While the ancient adherents of these positions agreed upon this common conclusion, they disagreed somewhat upon the arguments used to justify this conclusion.

St. Thomas describes the third erroneous position of the ancients on prayer as occupying a sort of middle position between the first two positions. On the one hand, those who held to this third position granted that human matters are indeed subject to God's providence. On the other hand, these same adherents rejected the notion that all things in the world come about of necessity. Rather, they held that human beings are able to initiate human acts, which are genuinely free. In addition, unlike the adherents of the first two positions, those who held to this third position affirmed the efficacy of petitionary prayer. We might think that so far this position sounds pretty good. And indeed it does, so far . . . Yet, as St. Thomas tells us, this position is severely problematic as regards how its adherents explain the efficacy of prayer. He says, "they deemed the decree of divine providence to be changeable, and that it is changed by prayers and other things pertaining to the worship of God." So, while this third erroneous position certainly affirmed the efficacy of petitionary prayer, it also just as certainly denied the absolute immutability of God's providence.

At this point, the reader might experience a slight case of déjà vu. At least, that's my hope. For at this point it should be clear that this third erroneous position on prayer, which St. Thomas has just described, is essentially the same as that position espoused by twentieth century process philosophers like Hartshorne and Ford. People like Hartshorne and Ford are hardly novel as regards their position on this matter. In fact, they're doing nothing more than recycling an ancient error, which St. Thomas definitely refutes.

So, how precisely does St. Thomas deal with these erroneous positions on prayer? And, in so dealing, how does the Angelic Doctor do away with the argument, which the process philosophers raise against Catholic doctrine? Although St. Thomas doesn't explicitly make this comment, I think that it is safe to say that he views these three erroneous positions on the efficacy (or lack thereof) of prayer as but three fatally flawed attempts to reconcile the nature of efficacious prayer with the immutability of divine providence. But the true position on this matter must unequivocally affirm both. Thus, St. Thomas tells us, "it behooves us so to account for the utility of prayer as neither to impose necessity on human affairs subject to divine providence, nor to imply changeableness on the part of the divine decree." That is, St. Thomas wants to make clear how the efficacy of prayer is compatible with God's unchangeable providence. Hereafter, St. Thomas presents us with his resolution to this theological difficulty. Here is his response in full:

In order to throw light on this question we must consider that divine providence decrees not only what effects shall take place, but also from what causes and in what order these effects shall take place. Now among other causes human acts are the causes of certain effects. Wherefore it must be that men do certain actions, not that thereby they may change the divine decree, but that by those actions they may achieve certain effects according to the order of the divine decree: and the same is to be said of natural causes. And so it is with regard to prayer. For we pray, not that we may change the divine decree, but that we may impetrate that which God has decreed to be fulfilled by our prayers, in other words "that by asking, men may deserve to receive what Almighty God from eternity has decreed to give," as Gregory says (Dial. 1.8).9

This resolution of St. Thomas is both straightforward and profound. He begins by telling us that divine providence decrees from eternity not only which effects will come about in the created order, but also which created secondary causes will bring about these effects as well as the order in which these secondary causes will bring about these effects. This follows from the notion of providence, which St. Thomas set before us at the beginning of this essay. As we saw above, he argues that since God is the Cause of things by his intellect and will, and since there must pre-exist in God an exemplar of every one of his effects, it is necessary that the exemplar of the order of things to one another and to their end must pre-exist in the divine mind. And, "this exemplar of things ordered to their end is, properly speaking, providence."10 Now, since the created secondary causes which God ordains to bring about certain effects in the created order must themselves be numbered among his effects, it follows that these secondary causes fall under the decree of divine providence.

Now it is clear that human acts are among these secondary causes of which we are speaking (although human acts in no way exhaust the secondary causes which St. Thomas has in mind). That is, it should be clear to all of us, from our experience, that our human acts really cause certain effects. Consider such quotidian human acts as making breakfast, gardening, and reading a good philosophy book. Each of these acts serves in one way or another as a cause of some specific effect. One might say that breakfast on the table, a well-kept garden, and an increase in knowledge are the effects brought about by the human acts just mentioned. At this point St. Thomas draws his first conclusion. Human beings perform certain human acts, not in an attempt to change God's unchangeable providence, but rather in order to bring about certain effects, which God has ordained to follow from the human acts in question. But petitionary prayer is amongst those certain human acts, which are ordered to the bringing about of certain effects. Therefore, we should say that petitionary prayer is not done in an attempt to change God's unchangeable providence, but rather in order to bring about those effects, which God has ordained to follow from the prayer in question.

We can see from this, then, that the efficacy of petitionary prayer is not opposed to God's unchangeable providence, but instead is included within it, so to speak. We must recognize that not only do the effects of our prayers fall under the scope of God's unchangeable providence, but so do our prayers themselves (as well as all of our human acts). As St. Thomas puts it so well, "we pray, not that we may change the divine decree, but that we may impetrate that which God has decreed to be fulfilled by our prayers."11

The objection, which the process philosophers make against Catholic doctrine, fails, then, because it begins with an impoverished view of divine providence, which is anything but the Catholic view. That is, the process philosophers' objection assumes that God's unchangeable providence somehow does not extend to the act of petitionary prayer itself, but only to its would-be effect. This, however, is not the case nor is it in accord with Catholic doctrine. It is from this impoverished view of divine providence, as well as from a desire to retain the reality of the efficacy of petitionary prayer, that the process philosophers are often led to their position which essentially coincides with the third erroneous view of the ancients which St. Thomas describes.

Even after the argument of the process philosophers has been done away with, another question not only remains but also seems naturally to grow out of St. Thomas's treatment of the relationship of efficacious prayer to God's unchangeable providence. The question I have in mind is this: If every human act (including but not exclusive to those human acts which involve petitionary prayer) falls within the scope of God's totally unchangeable providence, then how is it possible for any human act to be genuinely free? This, of course, is a version of the well-known theological question regarding the proper relation between human liberty and God's unchangeable providence. Although there certainly is an answer to this question, I shall not even attempt to provide it here in any of its fullness. However, it would be fitting, by way of conclusion, to mention a comment made by St. Thomas, which helps to point out part of the true answer to this question, although not in all of its specificity.

In one place where he addresses this question, St. Thomas begins by invoking an important principle of Dionysius the Areopagite, which reads thus, "It does not pertain to divine providence to destroy but rather to preserve the nature of things."12 St. Thomas then explains the meaning of this principle as follows:

Whence it [i.e., divine providence] moves all things according to their condition. Thus, from necessary causes, through the divine motion, effects follow of necessity and from contingent causes effects follow contingently. Because, therefore, the will is an active principle which is not determined to one thing, but rather has an indifference towards many things, God moves it in such a way that it is not determined of necessity to one thing, but such that its motion remains contingent and not necessary, except in those things to which it is moved naturally.13

Here St. Thomas is pointing out that divine providence is so all-comprehensive that it not only extends to those things that come about in the created order, but also to the way or the mode in which they come about. Thus, as regards our human acts, not only the acts themselves, but also the very freedom with which they are done is included under the all-comprehensive scope of God's unchangeable providence. How mysterious and wonderful this truly is.


1. See Charles Hartshorne's Omnipotence and Other Theological Mistakes (New York: State University of New York Press, 1984), 1-26. In this work Hartshorne makes it clear that he thinks that the notion of unchangeable providence is incompatible with human freedom. Although in this work Hartshorne doesn't explicitly formulate the argument, which I am going to attribute to process philosophers in general, nonetheless, one could see from this work of his that he would be quite sympathetic to such an argument. He does though hold to what is the essence of the third erroneous view of prayer, which St. Thomas attributes to the ancients (as will be seen below).

See also Lewis Ford's "Our Prayers and God's Passions," in H. J. Cargas and B. Lee (eds.), Religion, Experience and Process Theology (New York, 1976), 429-430. Here Ford explicitly formulates the argument, which I attribute to process philosophers in general. He sees this argument as being insurmountable for Roman Catholics. Indeed, he holds that only a process account of God is able to overcome the dilemma posed in this argument.

2. See, for example, Mt. 7:7-11; 21:22, Jn. 15:7 as well as CCC #2738-2741.

3. For example, Vatican Council I, Dei Filius, ch. 1.

4. ST 1.22.1c.

5. ST 1.22.2-3c.

6. ST 1.1.8c.

7. Vatican Council I, Dei Filius, ch. 3 and 4.

8. ST 2-2.83.2c. In what follows I give a summary of St. Thomas's treatment of whether it is becoming to pray.

9. ST 2-2.83.2c.

10. ST 1.22.1c.

11. ST 2-2.83.2c.

12. ST

13. ST

David Arias lives in Houston, Texas with his wife Jennaya and their two children. David is a graduate student at the Center for Thomistic Studies at the Univesity of St. Thomas. This is his first article for HPR.

© 2003 Ignatius Press

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