Every so often, the same point of controversy resurfaces across social media platforms. One such matter of dispute is the question of whether Muslims worship the one true God. Recently, this topic was raised on several popular platforms. Non-Catholics have been accusing Vatican II—and thus the Catholic Church—of teaching error when it says that Muslims do adore the one God. Such accusations provoked multiple responses from Catholic apologists.
I would like to acknowledge from the start that it is understandable if people find this teaching difficult to grasp. On the face of it, it can seem problematic. However, I encourage the reader to keep an open mind and to investigate the question further if need be.
While I cannot address all the arguments made on both sides in a brief article, I nevertheless want to provide some information about this oft-misunderstood issue. In the process, I hope to show two things: 1) Vatican II’s teaching is not new but, rather, is long-standing doctrine and 2) the Catholic position is entirely defensible. First, I will quote two passages from Vatican II about the matter. Second, I will cite some arguments against the Catholic position. Third and finally, I will offer counterarguments.
In Lumen Gentium 16, the Council Fathers write that “the Muslims . . . along with us adore the one and merciful God, who on the last day will judge mankind.” Similarly, Nostra Aetate 3 says that “[Muslims] adore the one God, living and subsisting in Himself; merciful and all-powerful, the Creator of heaven and earth.”
There are two related arguments that are often levied against this teaching. One argument states that, since Muslims do not worship Jesus, who is God, they do not worship the one true God. Similarly, some phrase it this way: Since Muslims do not acknowledge the dogma of the Trinity, they do not worship the true God, because the Trinity is the true God.
Before I offer counterarguments, I would first like to show that the teaching from Vatican II is rooted in prior Catholic teaching and theology. As one example, the passage from Nostra Aetate quoted above references a letter from Pope St. Gregory VII (d. AD 1085) to the Islamic king of Mauritania. In that letter (AD 1076), Gregory writes, “We and you must show in a special way to the other nations an example of this charity, for we believe and confess [the] one God, although in different ways, and praise and worship him daily as the creator of all ages and the ruler of this world”1 (emphasis added). Note that Latin does not have definite or indefinite articles. Thus, the exclusion of “the” before “God” is a matter of translation choice. In context, however, it is obvious that St. Gregory VII is affirming that it is one and the same God; otherwise, their closer bond than with other peoples would be meaningless. Mere monotheism does not suffice. Furthermore, the pope goes on to say that both parties “worship him”: two sets of worshipers, one object of worship.
Two people can be referring to the same third person while holding contrasting opinions about that person.
Similarly, the Catechism of St. Pius X (1910) under the ninth article of the Creed addresses the question “Who are infidels?” The answer is telling. Broadly speaking, it says, “Infidels are those who have not been baptised and do not believe in Jesus Christ.” However, it then subdivides infidels into two distinct categories based on the reason they do not believe in Christ: “because they either [1] believe in and worship false gods as idolators do, or [2] though admitting one true God, they do not believe in the Messiah, neither as already come in the Person of Jesus Christ, nor as to come; for instance, Mohammedans [i.e., Muslims] and the like” (emphasis added). This catechism from well before Vatican II makes an important distinction between idolators who worship false gods and Muslims who admit one true God (capital G).
This same understanding of different categories of infidels is also expressed in The Catholic Encyclopedia entry from 1910. It reads, “The term [infidels] applies not only to all who are ignorant of the true God, such as pagans of various kinds, but also to those who adore Him but do not recognize Jesus Christ, as Jews, [and] Mohammedans” (emphasis added).
Similarly, St. Robert Bellarmine, in his Controversy on the Word of God (book 3, chap. 10), writes, “Jeremiah foretold the future: that in the time of the New Testament all men will know the one God, which is certainly now fulfilled. For the Gentiles have been converted to the Faith, and also the Jews and the Turks [i.e., Muslims], who, although they are impious, still worship the one God.”2 Similar treatments are attributed to St. Thomas Aquinas and St. John Damascene. As Jimmy Akin recently pointed out, “This has been the traditional Catholic understanding. If you read traditional authors interacting with Islam—like St. Thomas Aquinas or St. John Damascene—they criticize it, but you don’t find them saying things like, ‘Muslims worship a different God from the God we Christians worship.’”
We turn now to the objection that, because they do not believe that God is triune, Muslims cannot believe or worship the true God. Some Catholic apologists and scholars have argued that a subset of people who make this argument apply it inconsistently insofar as they do not deny that Jews of Old Testament times and/or of today worship the true God, the God of Abraham, Isaac, and Jacob, despite not having an explicit knowledge of or belief in God as triune. Some people find this retort compelling, while others press against it.
Either way, there is another problem with the non-Trinitarian argumentation, at least from a Catholic perspective. It is Catholic dogma that the existence of God is knowable through natural reason.3 However, the fact that God is triune is not knowable by natural reason. Yet, it is the same God who is known via natural reason and who has revealed himself as triune. One can, then, know and adore the one God knowable through reason without knowing that God is triune. Accordingly, in his reply to objection 3 in the Summa theologiae 2-2.81.2, St. Thomas Aquinas states, “It belongs to the dictate of natural reason that man should do something through reverence for God.” This is the basis for the virtue of natural religion as understood in classical theism.
For similar reasons, the Thomist philosopher Dr. Edward Feser argues that Muslims and Christians worship the same God. To be clear, no one is arguing here that simply being a monotheist suffices to believe in or adore the one true God. If one believes in a single god who is akin to a superhuman, Zeus-like figure but not the metaphysical ground and source of all existence, etc., then one’s conception of divinity is not the same as that of Christianity or classical theism. One means something different by the term “God” or “divinity” than Christians and classical theists do. Hence, Feser argues, “Now, being metaphysically ultimate, being that from which all else derives, being that which does not have and in principle could not have a cause of its own, etc.—in short, being what classical theism says God essentially is—is, I would say, what is key to determining whether someone’s use of ‘God’ plausibly refers to the true God.” In other words, if one agrees with, say, Aquinas’s five proofs for the existence of God, then there is sound reason to conclude that the person affirms the existence of the one true God, even if they do not know additional information about God that comes through revelation.
In addition to the existence and attributes of God known through natural reason, one could have additional beliefs about God that are, in fact, false. One could believe in God as known through natural reason but hold false opinions about his activity in relation to humanity. For instance, Muslims falsely claim God authored the Quran. But holding this false belief does not mean they are referring to a different reality, only that they have some false beliefs about that reality. Accordingly, Feser appeals to the distinction between “sense” and “reference.” Two people can be referring to the same third person while holding contrasting opinions about that person.
Feser gives some worthwhile examples you can read for yourself, but let me offer another example. Let’s say the two aforementioned people both know an author named Joshua. One of them thinks Joshua wrote only one novel and that it is novel X, while the other person thinks he did not write that novel but a different novel, Y. Does it follow that they are not referring to the same person? No. It means at least one of them is wrong about which novel Joshua wrote. There are innumerable examples where two people can be referring to the same person or reality while expressing contrary beliefs about said person or reality.
I encourage the philosophically inclined to read Feser’s article further, since he elaborates much more than I have about the sense-reference dichotomy. He also engages with other philosophers’ arguments that are worth learning about.
The main point here has been to show that lacking belief in the Trinity does not itself negate belief or adoration of the one true God. Similarly, the one true God is the same God before and after the Incarnation, so lack of belief in Christ as God the Son Incarnate does not mean one does not know or adore the one God. While Muslims do reject truths about God that he has revealed and believe God has revealed things that he did not in fact reveal, they still have a shared conception of what Catholics mean by God and divinity with respect to natural theology or classical theism. This is augmented by the fact that Muslims explicitly affirm their belief that the one God is also the God of Abraham. This provides a basis for asserting that the referent of belief and adoration is the same, while certain beliefs about God with respect to salvation history are significantly different.
In conclusion, when the Catholic Church affirms that Muslims adore the one true God, it is not affirming that everything the Quran says about God is correct. It does not even hold that the Quran transmits divine revelation. It is not saying Muslims affirm all we know about God through authentic revelation. It is simply affirming that the referent of discussions about God and of the adoration given to him is one and the same reality, despite those differences. Insofar as Muslims affirm the existence of God as knowable through natural reason—despite making further, even false, claims about the one God with respect to salvation history—it is still sound to affirm they are directing their adoration to this one true God. To be clear, this does not mean their worship of God is on par with that of Christians. It only means the object of the worship is the same.
1 Gregory VII, “Letter to Anzier, King of Mauritania,” in The Christian Faith in the Doctrinal Documents of the Catholic Church, ed. Jacques Dupuis, 7th revised and enlarged edition (Alba House, 2001), no. 1002, p. 419.
2 This quote is taken from a comment by Dr. Robert Fastiggi posted under an article by Dr. Larry Chapp available here.
3 See First Vatican Council, Dei Filius, Dogmatic Constitution on the Catholic Faith (April 24, 1870), Chap. 2. See Denzinger 3004.