Answering Islam - A Christian-Muslim dialog


K. Dayton Hartman II

The Necessity of Trinitarian Apologetics

The historic, orthodox doctrine of the Trinity is entirely unique among the world’s religions.2 In light of this fact, there exists a temptation to ignore the Trinity when evangelizing Muslims. By omitting the Trinity from mission efforts, those reaching Muslims for Christ have failed to recognize that, as Timothy George has noted, “Bare monotheism divorced from the rich content of biblical faith is not enough. The doctrine of the Trinity is not peripheral, but essential to our understanding of the character and nature of the one God.”3. As a result, any mission effort that fails to address and contextualize the Trinity is not only unbiblical, but could be regarded as heretical. The Great Commission cannot be fulfilled if the Trinity is forgotten. This reality is made apparent when one considers the following facts.

First, the very act of the incarnation requires the efforts of the entire Godhead. The Father is the sender, the Son is the one sent, and the Holy Spirit empowers. The incarnation is the foundation of the Gospel, for without the incarnation there is no Gospel. The basis of the Gospel is the sacrifice of God in human form on behalf of humanity. Therefore, the Gospel message requires a triune God.  Second, Christian mission efforts are Christocentric, not Christmonistic.4 While the focus of all “mission” efforts is to introduce the lost to the Messiah, Christ Jesus, this is not the only focal point. At the very least, Christ’s role within the triune God must be addressed to ensure that those evangelized are coming to salvation in the true Christ.5 Third, it is impossible to separate the message of Christ from the Trinity. In the first two chapters of the book of Acts, the reader is informed that the power and work of the Spirit aids in evangelism. According to John’s Gospel, the convicting work of the Holy Spirit brings the lost to salvation in Jesus Christ.6 Therefore, one cannot address the need to recognize Christ as the Messiah without invoking the work of the Trinity. Finally, it is the goal of all mission efforts to bring people into a relationship with the one true God, so that they may glorify Him as the triune God.7 James White correctly observes: “We have to have knowledge of our God to worship Him correctly. If we have defective knowledge, or worse, if we have wrong information…our worship is either lessened, or it is completely invalid, as the worship of idols and false gods.”8 The doctrine of the Trinity is so intertwined with the saving work of Jesus Christ that it cannot be avoided nor neglected in reaching Muslims for Christ.

The Doctrine of Tawhid

The strength of Islam lies in its absolute adherence to monotheism. Denying the existence of all other deities, Islam represents the most rigid form of monotheism among the world’s monotheistic religions. The fundamental article of faith in Islam, the shahada,9 affirms that “There is no God but Allah.”10 It is through its devotion to the oneness of God that Islam has expanded.

The monotheism of the Qur’an could be summarized in Surah 112:1-4: “Say: He is Allah, the One and Only; Allah, the Eternal, Absolute; He begetteth not, nor is He begotten; and there is none like unto Him.” In his commentary on this passage, Yusuf Ali readily admits that the intent of this Surah is the negation of the Christian conception of the Godhead.11 The doctrine of the Trinity is perceived as beyond the teaching of Scripture, as Muslims believe that there is nothing in the divine books (the Old Testament and Qur’an) which reveals any triune concepts.12 Further, the doctrine of the Trinity is seen as ludicrous for allegedly violating the basic rules of logic. A common objection raised is: “How can God be one and three at the same time? It is absurd, rationally impossible, and mathematically wrong. Unity and Diversity cannot gather together.”13 In addition, some Muslim scholars reject the Trinity because they believe that it is impossible for two persons sharing equal power to exist without some type of power struggle or collision.14 Consequently, there can be but one divine person.15 Thus, Muslims object to the Trinity, not only because it violates the description of Allah in the Qur’an, but because it is believed to be logically impossible.

Answering Muslim Objections to the Trinity

In describing the absolute unity of Allah, Muslim theologians paint a picture of undifferentiated unity. However, undifferentiated unity is only a mathematical possibility rather than a physical reality. If one were to look unto the natural order to find an example of undifferentiated unity, nothing would be discovered. In fact, rather than undifferentiated unity, nature reveals a multitude of examples for plural unity. Timothy Tennent gives the following illustration:

A stone has little internal differentiation. If you split a stone in to two pieces, you have not destroyed the essence of the stone; you have created two smaller stones. However…If you cut a tiger in to two pieces, you do not get two smaller tigers. In the act of dividing the tiger you destroy the very essence of the tiger. A tiger, although a complex and internally differentiated creature, has an indivisible essence because it cannot be separated without destroying that essence.16

The complexity of the tiger is undeniable; however, his unity is even greater than the unity of one of the most basic objects on earth, a stone. From this illustration, the following facts can be established. First, complexity does not negate unity. An object can be complex, yet entirely unified. Second, internal differentiation does not contradict absolute unity. In fact, it is external differentiation that runs counter to unity.  Last, throughout the created order, illustrations of complex unity can be presented. These examples range from common mammals to human beings. For example, the human body is an instance of unity possessing complexity. The essence of a human being is unified, yet there is plurality in its parts. For instance, the ears and eyes are fully parts of the body yet each is unique from one another in structure and function. Despite sharing in the same essence, the ears hear and the eyes do not; likewise, the eyes see and the ears do not.17 At any given moment one could say that they see and yet they do not see; that they hear and yet they do not hear.18 This does not represent a contradiction because the distinct portions of the body share in a unified essence.19 While different from one another, the parts of the body would cease to function if they were to be separated from the essence of the body. Thus, plurality and unity are entirely compatible.20

A Knowable God

The example of plural unity within the creation is undeniable. As a result, a Muslim may object to the use of the created order as analogous with the nature or essence of God. However, such an objection would be unfounded because the Qur’an uses a plethora of anthropomorphisms to describe the nature and actions of Allah.21 In light of this, to claim as the Qur’an does, that Allah is beyond description or analogy is logically self-defeating.22

If Allah is beyond description, then nothing meaningful could be said regarding Allah. In this scenario one could not say that Allah “knows” anything, for the human understanding of “knowledge” can only be compared with human experience. Likewise, if one were to say that Allah “loves” or is “compassionate,” he would be making a nonsensical statement. The only referent by which one is to understand “love” and “compassion” is human experience and action. If one denies that these characteristics could be analogous to those of Allah, then he is left with no way to know that Allah possesses “love” or “compassion.” Such a position would negate the information regarding Allah ascertained from his ninety-nine beautiful names.23 With the majority of Sunni Muslims understanding these names to be adjectival descriptions of Allah’s divine attributes, such a negation would be quite damaging to Islam’s theological landscape.24

If one continues in his insistence that Allah is beyond description, he falls into the proverbial “rock and a hard place.” By claiming that one cannot describe Allah or know Allah through analogy, he has made a self-contradicting statement. For if nothing can be known of God through any imagery in the created world, one could not know that the imagery of the created order provides no insight into the nature and essence of Allah. To propose that the created order bears no resemblance to Allah is to claim to know something, albeit negative, about Allah’s nature that one could not possibly know. In essence, one has stated that they know that nothing can be known of Allah’s nature. What one is left with then is absolute agnosticism.

The objection could be raised that Allah has no essence; that is to say, his nature is beyond anything we can "know" because there is no “nature” to be known. However, such a claim would, again, be inconsistent. Muslims believe that Allah is the eternal, necessary being. However, if Allah is necessary, “…he must have a nature or else he could not be by nature a necessary kind of being.”25 If Allah’s nature does not necessitate his eternality, then he would not be eternal. Thus, to object to the use of analogy in describing the nature of Allah, the Muslim must disregard the Qur’an’s use of anthropomorphisms and retreat into theological agnosticism.

Are Muslims Binarian?

The supposed eternality of the Qur’an carries with it significant implications in discussing the Trinity with Muslims.  This is because the Qur’an presupposes its own eternality and preservation. According to the Qur’an, Allah is in absolute isolation. He exists in total solitude with nothing beside him except for the Qur’an itself. Surah 85:21-22 reads: “…this is a Glorious Qur’an (inscribed) in a Tablet Preserved.” In his commentary on this Surah, Yusuf Ali readily admits that this passage conclusively demonstrates that the Qur’an is eternal.26 Additionally, in Surah 43:4, the Qur'an is described as being in the mother of the book. It is the source of revelation and exists eternally in the presence of Allah.27 According to Arthur Jeffery, “The Qur’an is Allah’s speech, not a created thing…”28 Because Allah’s speech (kalimah) is eternally part of his nature, the Qur’an must therefore be eternal as well.29 After observing the relevant material, Ignaz Goldhizer writes: “Speech is an eternal attribute of God, which as such is without beginning or intermission…consequently…the Qur’an has existed from all eternity. The Qur’an is uncreated.”30 With a number of Muslim theologians31 asserting the eternality of the Qur’an and with the preponderance of Sunni Muslims agreeing with this assertion, one must question as to how this differs from the Christian notion of Trinity.32 If speech is an eternal attribute of God, and the Qur’an has existed eternally alongside of Allah, would this not open the door for plurality within unity? If the Qur’an is in some form an attribute of Allah’s essence, yet it is eternally distinct from Allah, then how is this different from the concept of the Trinity proposed by orthodox Christians? Undeniably, if the Qur’an is eternal, as the attribute of Allah’s speech, and yet exists distinctly in the “preserved tablet,” this is analogous to the Christian conception of Trinity.

Muslims believe in two eternal things, yet they are, without question, monotheists.33 All three members of the Trinity are distinct from one another, yet all exist eternally in the same essence. This is represented in John 1:1. According to the Apostle John, Jesus Christ eternally existed alongside God the Father, yet there is but one God; Christ was with God and was at the same time God.34 In light of a belief in the eternality of the Qur’an, it would be incorrect and inconsistent for the Muslim to object to the Trinity because the doctrine proposes that all three members of the triad share fully in the divine essence.35

For one to claim that the Trinity is illogical on the basis of shared essence, he must also deny the eternality of the Qur’an. “In other words, the basic Muslim logic of either monotheism or polytheism (which includes tritheism) is invalid.”36 The fundamental beliefs of Islam presuppose some type of binarian eternality. Consequently, only if Muslims allows for the possibility of Trinitarian eternality can they continue to logically and consistently maintain their conception of the eternal nature of the Qur’an. To disallow plural unity would render the doctrine of the Qur’an’s eternality null and void. If Islam loses the doctrine of eternal speech then it also loses Muhammad’s verification of apostleship.37 Once Muhammad has lost his apostolic credentials, his message becomes meaningless. Therefore, a denial of the orthodox doctrine of the Trinity not only cuts to the heart of Christianity, but logically destroys the fundamental basis of Islam. Therefore, the Muslim would do well to consider the viability of Trinitarian, plural-unity in light of the Qur’an’s eternal existence. Just as the Qur’an is Allah’s eternal word, so is Christ the Father’s eternal Word; they are unified in essence yet distinct in person.

The Superiority of the Trinity

The doctrine of the Trinity far surpasses the Qur’an’s presentation of God’s nature in philosophical coherence and beauty. The Qur’an’s description of Allah is rife with inconsistencies. The God of Scripture, however, holds up under philosophical scrutiny. What follows will be a number of aspects representing the superior elements of the Trinity over tawhid.

First, the doctrine of tawhid fails to explain the human desire for love and community. According to Scripture, man is made in the image of God. This does not mean we resemble God physically, for God is a spirit, but rather that we share God’s qualities of mind, will, and emotion. In addition, we share God’s desire for community. In tawhid, all is consumed into the “one.” Within Islam there is no theological basis for human community. This is because, prior to creation, Allah was not relational because he existed in total isolation. One must remember that theology precedes anthropology. Consequently, if Allah does not exist in community, there is no basis for human community. Likewise, there is no rational foundation for assuming that the personal can originate from that which is impersonal. A monad god could not create beings who desire community. In contrast to this stands the God of the Bible. As the eternal being of love, which exists in three persons, the Trinity is an eternal community of absolute unity. The Trinity is relational, therefore mankind, as a reflection of God is relational and desires community.

Second, because Yahweh desires community, He is accessible to His creation. Allah is impersonal and unreachable. The God of Scripture desires fellowship with His creation.  Without this relational basis God could not reveal Himself to His creation. If Allah is not a “person” in the relational sense, then he is incapable of revealing himself. As result, no one, not even the prophets, could claim to know anything concerning Allah. Yahweh is relational; therefore, it is theologically consistent to assume that Yahweh can and does reveal Himself. Additionally, Scripture stresses the intimate nature of God. He literally acts as Abba, Father, to all who trust in the finished work of His Son, Jesus Christ. The doctrine of tawhid renders Allah unable of engaging in a relationship with his creation. Therefore tawhid, anthropologically speaking, is inferior to the doctrine of the Trinity.

The Philosophical Coherence of the Triune God

The philosophical description of the Trinity that follows not only presents a philosophical basis for the relational attributes of the Trinity, but also further demonstrates the superiority of the Trinity over and above tawhid. The purpose of this exploration is not to defend the Trinity against all charges of incoherence, but rather to address concepts vital in presenting the Trinity to Muslims.

When describing the Trinity in philosophical terms, one may inadvertently insist upon three divine beings; however, if this insistence occurs, it does so in direct opposition to the historical doctrine of the Trinity.38 Simply stated, the orthodox doctrine of the Trinity depicts God as three persons, yet a single divine essence.39According to Richard Swinburne, the existence of three divine persons is plausible.40 This does not mean, however, that three necessary beings or separate individuals exist.41 Instead, the possibility remains for more than one divine person to exist, providing that their generation is found within one another.42 More than one omnipotent person cannot exist unless omnipotence is grounded within a mechanism distinguishing a hierarchy.43 That proposed mechanism is God’s essence. From within the essence appear the functional titles of the Trinity. The Father is eternally in the role of Father, not because of any advantage in deity over the other persons of the Trinity, but rather in His functional role. Likewise, the Son and Spirit take their names as a result of their functional activity. This means that, while there is functional subordination within the Trinity, there is no ontological subordination.44

How can three persons exist within a single essence? God, by definition, is simple; that is to say, He is indivisible not that His essence is lacking complexity.45 If His essence were divided, He would not be God. This fact, however, does not negate the plurality of persons within the Trinity. Plurality is possible in the sense that tri-unity is intrinsic to the divine nature or essence of God.46 While one could call the Father alone “God,” this title would not qualify as a statement of absolute identification.47 Each member of the Trinity is not an individual instance of divinity, but rather is divine because tri-unity is inherent to deity. This principle does not defy the law of non-contradiction, and is on that basis logically coherent. Norman Geisler describes the argument as follows: “(1) God is one and only one in relation to His essence; (2) God is more than one (viz., three) in relation to His persons. These are two different senses or relations. Therefore, the Trinity is not contradictory.”48

Augustine’s analogy of love is quite useful in describing the necessity of the triune nature of God. If God is Love ontologically, He necessarily requires someone to love in order to exist. For a being that is absolute love to exist as an eternal, necessary being, He must have an object of love. In addition, for God to be perfect love, He necessarily must be plural. Richard Swinburne has noted that, “There is something profoundly imperfect and therefore inadequately divine in a solitary divine individual. If such an individual is love, he must share, and sharing with finite beings such as humans is not sharing all of one’s nature and is therefore imperfect sharing.”49 Undoubtedly, a perfect, ontologically divine love demands plurality. Merely two persons would not logically resolve this issue. While two persons can love one another, this type of love is individualistic. A perfect love demands some type of shared, selfless love. This is only accomplished while three persons exist within the Godhead. As Augustine has noted, there must be a lover, one being loved, and the power, or Spirit, of love. Therefore, any being that can be rightly described as “love” must exist in plurality. This plurality does not lend itself to polytheism, for, as Occam has pointed out, there is no need to unnecessarily multiply a number of entities. For the purpose of ontological, perfect love, only three divine persons are needed. Stated concisely, the doctrine of the Trinity may be beyond human comprehension, but it is not irrational.


The Trinity provides a coherent understanding of God’s nature, whereas tawhid crumbles under careful scrutiny. Illustrations for plural-unity pervade the natural order yet one fails to find any object representing undifferentiated unity. Additionally, the Muslim notion of the Qur’an’s eternality screams of plural-unity. If one denies plural-unity, one must also deny the eternality of the Qur’an; thereby destroying the foundation of Islam. Furthermore, the doctrine of the Trinity provides a clear explanation and theological basis upon which one can understand the human desire for love and community. Prior to creation, Allah was non-relational. As an inherently, non-relational being, Allah would be incapable of providing a basis for human community. Finally, the doctrine of the Trinity provides an explanation for the human pursuit of love. Because the Trinity has existed for all eternity in a community of love, the human desire for love springs forth from mankind’s reflection of the divine.  Without a Creator who possesses plural-unity, such an expression would be impossible. How then can one insist upon adhering to a cold and barren monotheism? The Trinity conveys the overwhelming brilliance of a loving God Who exists in a vibrant community of love.  Therefore, the church must not shy away from confronting Islam with the tri-unity of God.


1 This article was originally presented as a paper to the International Society of Christian Apologetics and can be accessed at their web address by following this link:

2 Millard Erickson, Christian Theology: Volume One (Grand Rapids, MI: Baker Books, 1983), 340. There are those who point to the Hindu god, Ishvara as a type of Trinity. Ishvara manifests himself in the form of Brahman, Vishnu and Shiva. This differs from the Christian doctrine in that this is not a single god revealed in three persons; it is three gods who are all manifestations of a single transcendent “one.”

3 Timothy George, Is the Father of Jesus the God of Muhammad? (Grand Rapids, MI: Zondervan, 2003), 81

4 Tormod Engelsviken, “Three Missiological Perspectives: What Testimony?” International Review of Mission, Vol. 95, No. 378/379 (July-October 2006), 330. By Christocentric it is meant that mission efforts primarily focus upon the person of Jesus Christ. That is to say Christ and His finished work take center stage in the presentation of the Gospel. However, recognition is given to the work of the entire Godhead. Christmonistic on the other hand means that the mission effort focuses solely upon the person of Jesus Christ. Christ’s atoning work alone is given primacy. There is little to no mention of God’s tri-unity.

5 For example, Mormon missionaries preach “Christ crucified,” however, this Christ is not an eternal member of the Godhead. Instead, he is the “begotten” (in the biological sense) son of God the Father and the virgin Mary. As result, it becomes apparent that an emphasis must be placed upon Christ as the eternal, second member of the Trinity.

6 John 15:26-27

7 Engelsviken, 331.

8 James White, The Forgotten Trinity (Minneapolis MN: Bethany House Publishers, 1998), 194.

9 Abul A’la Mawdudi, Towards Understanding Islam, (New York: BestWords, 1998), 75.

10 This is referred to as “the confession.” The entire confession, always recited in Arabic, is translated as follows: “There is no God but Allah, Muhammad is the Messenger of Allah.”

11 Yusuf Ali, The Meaning of the Holy Qur’an (Beltsville, MD: Amana Publications, 2006), 1714.

12 Ibn Taymiyya,  A Muslim Theologian’s Response to Christianity (Delmar, NY.: Caravan Books, 1984), 256. Cf.  W.M. Baagil, Christian-Muslim Dialogue (Kuwait: Revival of Islamic Heritage Society, 1980), 16.

13 Shabir Ahmad Usmani, The Noble Qur’an: Tafseer-e-Usmani (New Delhi: Idara Isha’at-e-diniyat, 1990), 1:ii.

14 Surah 21:22

15 Abul A’la Mawdudi, 83.

16 Timothy Tennent, Christianity at the Religious Roundtable (Grand Rapids, MI: Baker Academic, 2002), 158.

17 Ibid, 163.

18 Ibid.

19 Ibid.

20 It should be pointed out that physical analogies for the Trinity oftentimes can be broken down in such a way as to support tritheism or modalism. The physical analogy presented in this paper does not suffer from such a problem for the following reasons. (1) If any distinct portion of the body is separated from the body it does not become a self-sustained instance of human essence that is autonomous from the original host essence.  (2) If for example, the eye is removed from the body it does not become a separate instance of human essence. By being divided from the body, the eye has become a useless collection of developed genetic material. In addition, this genetic material is destroyed and dies upon being separated from the body. Thus, the human body, as an example of complex unity, does not breakdown in such a manner as to support tritheism or modalism.

21 Surah 38:71-72, 75; 49:1; 55:27. Regarding this phenomenon, Ali Dashti comments: “The belief that Allah has hands, fingers, a face, feet, and eyes…is not held by fringe Muslim sects but by the most fundamental scholars. It is held so strongly that anyone who denies this belief is considered an infidel in the eyes of some of those scholars.” Ali Dashti, Twenty Three Years: A Study of the Prophetic Call of Muhammad (London: George Allen & Unwin, 1985), 157.

22 Surah 6:104 “No vision can grasp Him, but His grasp is over all vision: He is above all comprehension, yet is acquainted with all things.”

23 The Surah, from which the ninety-nine beautiful names are derived, reads as follows: “Allah is He, than whom there is no other god—who knows (all things) both secret and open; He, Most Gracious, Most Merciful…The Sovereign, the Holy One, the Source of Peace, the Gaurdian of Faith, the Preserver of Safety, the Exalted in Might, the Irresistible, the Supreme…He is Allah, the Creator, the Evolver, the Bestower of Forms. To Him belong the Most Beautiful Names…He is the exalted in Might” Surah 59:22-24. The remainder of the ninety-nine names are found in the traditions recorded in the Hadith.

24 Kenneth Cragg, The Call of the Minaret (New York: Oxford University Press, 1964), 41-42.

25 Norman Geisler & Abdul Saleeb, Answering Islam: The Crescent in Light of the Cross (Grand Rapids, MI: Baker, 2002), 140.

26 Yusuf Ali, 1630.

27 Surah 43:4 “And verily, it is [the Qur’an] in the Mother of the book, in Our Presence, high (in dignity), full of wisdom.”

28 Arthur Jeffery, Islam: Muhammad and His Religion (New York: Bobbs-Merrill Company Inc, 1958), 92.

29 Allah as a speaking being is seen throughout the Qur’an: Surah 4:164; 7:143; 2:253; 42:51.

30 Ignaz Goldhizer, Introduction to Islamic Theology and Law (Priceton,N.J.: Priceton University Press, 1981), 97.

31 Such as Yusuf Ali, Ignaz Goldhizer, Yusuf Ibish, and Maulana Ali.

32 Sunni Muslims comprise approximately 86% of the world’s Muslim population.

33 Keith Swartley, ed., Encountering the World of Islam: Gospel Communication from Within by Patrick Cate (Atlanta: Authentic Media, 2005), 288.

34 John 1:1 “In the beginning was the Word, and the Word was with God, and the Word was God.”

35 Tennent, 163.

36 Geisler & Saleeb, 140

37 Surah 10:37-39 “This Qur'an is not such as can be produced by other than Allah. On the contrary it is a confirmation of (revelations) that went before it, and a fuller explanation of the Book - wherein there is no doubt - from the Lord of the worlds. Or do they say, ‘He forged it’? say: ‘Bring then a Sura like unto it, and call (to your aid) anyone you can besides Allah, if it be ye speak the truth!’ Nay, they charge with falsehood that whose knowledge they cannot compass, even before the elucidation thereof hath reached them: thus did those before them make charges of falsehood: but see what was the end of those who did wrong!”

38 If one proposes three divine beings, regardless of their functional unity, they are no longer ascribing to monotheism. Instead they have adopted a position called tri-theism. In tri-theism there are three necessary beings acting together as one, whereas Christian theism proposes that there is but one divine being revealed in three persons. See Norman Geisler. Systematic Theology Volume Two: God & Creation, 271.

39 Norman Geisler, Systematic Theology Volume Two: God & Creation (Bloomington, MN: Harvest House Publishers, 2003), 278.

40 William Lane Craig, ed.  Philosophy of Religion: A Defense of the Doctrine of the Trinity. By Richard Swinburne (New Brunswick, NJ: Rutgers University Press, 2002), 556.

41 It should be pointed out that Swinburne goes too far in His discussion of the persons of the Trinity and comes awfully close to presenting a Christianized version of polytheism. He appears to quasi assert that there are three instances of deity.

42 Swinburne, 558.

43 Ibid, 557.

44 Geisler, 290.

45 Ibid, 39.

46 William Lane Craig & J.P. Moreland, Philosophical Foundations for a Christian Worldview (Downers Grove, IL.: InterVarsity Press, 2003), 590.

47 Ibid.

48 Geisler, 292-293

49 Swinburne, 566.

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