What We Believe

The Reformed Faith and the Challenge of Islam

John Muether

When the Orthodox Presbyterian Church was founded in 1936, there were few Islamic mosques in America. The first one was established only 21 years earlier in Biddeford, Maine. A century later, there are now over two thousand. One of the newest opened last fall just north of Orlando, Florida. The Masjid Al-Hayy is a 43,000-square-foot domed building with a 130-foot-tall minaret. The $16 million building includes three million pounds of white marble from Greece. Its elaborately carved doors are made from Honduran mahogany, and Italian mosaic tiles grace the hallways. Thick silk carpets accommodate worshipers who kneel below custom-made chandeliers from Egypt in the prayer room.[1]

Ambitious construction plans are necessary to accommodate the sky-rocketing growth of Muslims in America, from 200,000 in 1950 to 3.5 million today (and more than doubling since 9/11). It will double again, by 2050, when it will become the second largest religion in the United States, surpassing Judaism. Orthodox Presbyterian ministers today serve in a very different world from the denomination’s founders, and the very public face of American Islam is a reminder that it is not just a subject for foreign missionaries anymore. Orthodox Presbyterian pastors, elders, and deacons need to reckon with a basic understanding of Islamic faith and practice to minister effectively in America today. Ten years ago in the pages of Ordained Servant, Dr. Bryan Estelle suggested ways in which the OPC should respond to the challenge of Islam.[2] I wish to supplement Dr. Estelle’s helpful article by pointing out some strategies that are popular but may be counterproductive and even a hindrance to faithful Christian witness to the Muslim world.

While many Christians perceive Islam as a relatively recent threat to the Christian West, this is a great misunderstanding. If the collapse of the Ottoman Empire after World War I prompted a brief dormancy in Islam’s public face, the threat to the West was well established long before. The Reformers of the sixteenth century, for example, were keenly aware of the threat of the Turks on the eastern border of Europe. Protestants and Catholics, Popes and Emperors alike, were nervously looking at the eastern border of Europe, where Turks were making menacing threats. Even after the Turks were repelled at the gates of Vienna in 1529 the threat was not over. In 1541 Luther wrote his “Appeal for Prayer against the Turks,” in which he expressed the fear of imminent invasion by the Turks. This was a just chastisement of God for the sins of the German people, he wrote in a tone that was grim and gloomy, even while he regarded it as his pastoral duty to prepare Germans for a likely invasion.

To ignore centuries of Christian reflection on Islam is not only an exercise in historical myopia; more seriously, it is to cut ourselves off from the wisdom and insight of voices in our Reformed past. Few today have studied the Islamic world in a more sustained and systematic way than Samuel Zwemer (1867–1952). Zwemer was a pioneering Reformed missionary to Arabia and Egypt for twenty-eight years and later Professor at Princeton Theological Seminary.[3] He earned the nickname, “Apostle to Islam” for his devotion for carrying the gospel of Christ to the Muslim world, even though his labors witnessed only a small handful of converts to Christ. His devotion to the study of Islam included his thirty-five-year tenure as editor of The Muslim World. Zwemer urged that Christian workers devote themselves to the study of Islam:

Ignorance of the Koran, the traditions, the life of Mohammed, the Moslem conception of Christ, social beliefs and prejudices of Mohammedans, which are the result of their religion— ignorance of these is the chief difficulty in work for Moslems.”[4] Toward the end of his life, Zwemer was fond of telling students that “only the Reformed faith can witness effectively to Islam.[5]

Acknowledging the Diverse Expressions of Islam

One popular misconception today is to imagine Islam as a unified and monolithic religion. The Islamic world is remarkably diverse. How can diversity not characterize a religion of 1.6 billion adherents? For comparison’s sake, consider this diverse list of religious groups:

  • Roman Catholics
  • Unitarians
  • Charismatics
  • Seventh Day Adventists
  • Mormons
  • Jehovah’s Witnesses
  • Mainline Protestants
  • Confessional Presbyterians

What do these all have in common? Precious little, we might imagine. But they share at least this much: all of them are lumped together as “Christian” by demographers of world religions. They and many others comprise the 2.1 billion who are numbered among the total world population of Christians. We might object to such broad-brush use of the term Christian; its vague description seems hardly useful.

But if we insist on distinguishing ourselves from others who claim the term Christian, we owe the same courtesy to the Muslim world. Most of us are at least aware of the differences between Sunni and Shia Islam. The two sects diverged soon after the death of Prophet Muhammad over who should succeed him. But that does not begin to account for the diversity in Islam. Muslims express their faith in many ways, including:

  • Folk Islam
  • Orthodox Islam
  • Secular Muslims
  • Ambivalent Muslims
  • Mystics
  • Fundamentalists
  • Militant Fundamentalists

The last category consists of less than 7% of the world-wide Islamic population by informed estimates, but most Western Christians struggle to imagine any other form of Islam. Diversity of contemporary Islamic faith and practice serves to warn us of the danger of approaching this subject in simplistic or reductionistic terms. It is vital that we neither romanticize nor demonize the challenge of Islam. Islam is not inherently peaceful, and Islam is not inherently violent. Rather, Islam is complex in its diversity of expressions, and Christians must not let radical Islam radicalize their response.

How then ought we to regard the peaceful overtures from many quarters of the Muslim world? Samuel Zwemer did not hesitate to read these as signs of the work of the Holy Spirit among Muslims, and he attributed this to the Reformed doctrine of common grace:

Whatever be the doctrine of the Holy Spirit in Islam, we know that for those in contact with Islam, as missionaries, every virtue these [pious Muslims] possess, every victory won, every thought of holiness, every deed of kindness, every ministry of love, is his alone. It is God’s common grace that enabled them, as even Calvin taught.[6]

Here Zwemer demonstrates that Calvinism can account for the diversity of Islam, both in its peaceful and violent expressions.

Abrogation: Muslim and Christian

When my students at Reformed Theological Seminary read sections of the Qur’an, they are surprised at several unusual features. Sometimes they encounter beautiful sections of sublime poetry such as the following:

God: there is no god but Him, the Ever Living, the Ever Watchful. Neither slumber nor sleep overtakes Him. All that is in the heavens and in the earth belongs to Him. Who is there that can intercede with Him except by His leave? He knows what is before them and what is behind them, but they do not comprehend any of His knowledge except what He wills. His throne extends over the heavens and the earth; it does not weary Him to preserve them both. He is the Most High, the Tremendous. (2:255)

If that vaguely resembles the Psalms, it is not coincidental. Islam considers the Torah, the Psalms, and parts of the Gospels as revelations from Allah. This is what Zwemer described as “borrowed elements” in the Qur’an. It is comprised of Jewish, Christian, and pagan sources (although the Hebrew Scriptures and the New Testament are regarded by Muslims as defective and corrupt versions of revelation).

There are parts of the Qur’an that seem to portray Muslims as the champions of religious liberty. “There is no compulsion in religion,” we read in 2:256. On the other hand, there are so-called “sword verses” that deny any form of tolerance:

Believers, those who ascribe partners to God [i.e., Trinitarians] are truly unclean: do not let them come near the Sacred Mosque after this year. If you are afraid you may become poor, bear in mind that God will enrich you out of His bounty if He pleases: God is all knowing and wise. Fight those of the People of the Book who do not truly believe in God and the Last Day, who do not forbid what God and His Messenger have forbidden, who do not obey the rule of justice, until they pay the tax and agree to submit. (9:29)

So which is it: does the Qur’an teach a peaceful or violent encounter between Muslims and other “People of the Book?” How can these passages be reconciled? Muslims appeal to the doctrine of “abrogation” to explain many of these apparent contradictions. Simply put, some of Allah’s commands are marked for expiration; that is, later revelation replaces earlier revelation. “Any revelation We cause to be superseded or forgotten, We replace with something better or similar” (2:106). Similarly, “When we substitute one revelation for another––and God knows best what He reveals–– they say, ‘You are just making it up,’ but most of them have no knowledge” (16:101).[7]

Christians may dismiss the principle of abrogation as an awkward feature of the Qur’an that reveals its patchwork, human origins. But is there a similar hermeneutic of abrogation from Christians voices? Dispensationalism can sound a very similar note: God had a plan for Israel, the rejection of which led to his offering a “Plan B” to the Gentiles. Sometimes this goes by the term “replacement theology,” and it is a reading of Scripture that plays right into the Muslim doctrine of abrogation.

Consider how Muslims regard the parable of the laborers in the vineyard, where Jesus describes morning, noonday, and evening laborers, and draws the conclusion that “the last will be first, and the first last.” Muslim interpretation points to Judaism as the morning laborers, the apostles of Christ the noonday laborers, and Muslims as the evening laborers, the last who are now first. Similarly, when Jesus told the Samaritan woman that the hour was approaching when God will be worshiped “neither on this mountain nor in Jerusalem” (John 4:21), Muslims insist that he was really demonstrating that Allah’s true followers would worship him in Mecca.

In other words, if Plan B is God’s response to Jewish stubbornness and rebellion, is it too much of a stretch to conceive of Islam as Plan C? A dispensational hermeneutic of discontinuity cannot display to the Muslims the beauty of Scripture in its unfolding of redemptive history. It is essential for Christian apologetics to the Muslim world to advance the hermeneutic of promise and fulfillment. The living and true God is a covenant-keeping God. He does not change his mind; rather, he keeps his promises. There is one plan of salvation and one people of God. The work of Christ is portrayed by the patriarchs and predicted by the prophets, and all of God’s promises to his people are fulfilled in Christ.

The Folly of the “Outsider Movement”

Can converts to Christ in Muslim-dominated cultures remain in their Muslim world and even maintain many of the practices of Islam? A growing trend in Christian missions today encourages Muslim converts to do just that. This is known as the insider movement: Muslim converts to Christ are “completed Muslims” (just as Messianic Jews are “completed Jews”), who should find it possible to remain in their Muslim culture. Some missiologists go so far as to claim that such converts can still accept Muhammad as their prophet. After all, he led them to the one true God and he spoke highly of Jesus in the Qur’an.

We dare not make light of the sacrifices required of Muslims in coming to Christ. Converts to Christ in Muslim majority countries can experience the demand to “let goods and kindred go” in painful ways that Western Christians can barely imagine. But many Muslim background believers know that they cannot have Christ in any other way: a Christianity that does not offend is not a gospel that will impact the Muslim world.

This view might be more accurately described as the outsider movement, because it consigns Muslim converts to a Christian life without the church, outside of which there is no ordinary possibility of salvation (WCF 25.2). By withholding from converts the privilege of numbering among the people of God, in fellowship with God and his people, the Christian missions are keeping from them the joy of communion of saints and the means of God’s appointment for their growth in grace.

The objection may be raised: Isn’t the effort to contextualize simply a way to follow Paul’s command and be “as Muslims to the Muslims?” Here we can turn again to Zwemer, who anticipated this argument a century ago. “We must become as Moslems to the Moslem if we would gain them for Christ,” he insisted. But then he went on to add: “We must do this in the Pauline sense, without compromise, but with self-sacrificing sympathy and unselfish love” (emphasis added).[8]

Moreover, upon closer inspection, some of these efforts at contextualization do not involve being Muslims to the Muslims but being evangelicals to the Muslims. That is, they display more evangelical biases than sensitivities to the Muslim community. Specifically, what is at work here is a low view of the church and a disregard for its shepherding and discipline in the Christian life that is all too common among contemporary evangelicalism.[9]

Disguising the Trinity

The concept of the Trinity is an abomination to Islam, and the Qur’an is unrelenting in its condemnation of this heresy, in passages such as this:

People of the Book, do not go to excess in your religion, and do not say anything about God except the truth: the Messiah, Jesus, son of Mary, was nothing more than a messenger of God, His word, directed to Mary, a spirit from Him. So believe in God and His messengers and do not speak of a ‘Trinity’—God is only one God, He is far above having a son, everything in the heavens and earth belongs to Him. (4:170–71)

In light of these texts, should we present Christ to Muslims in a more accessible way than to call him the “Son of God”? Should we describe the Christian Godhead in more subtle ways that will prompt less offense to the radical monotheism of Muslims? Some Bible translators are doing just that, and here are a few examples.

  • Matt. 28:19 – “in the name of the Father, the Son, and the Holy Spirit” becomes “in the name of God and his Messiah and the Holy Spirit.”
  • Luke 1:32, 35 – “Son of the Most High” and “Son of God” become “the awaited Christ.”
  • Luke 4:3, 9 – “the Son of God” becomes “the Messiah of God.”
  • Luke 6:36 – “your Father is merciful” becomes “God is merciful.”
  • Luke 11:2 – “Father” in the Lord’s Prayer becomes “Our loving heavenly Lord.”

Samuel Zwemer refused to disguise the Trinitarian character of the Christian faith:

Islam is proud to write on its banner, “the Unity of God;” but it is, after all, a banner to the Unknown God. Christianity enters every land under the standard of the Holy Trinity—the Godhead of Revelation. These two banners represent two armies. There is no peace between them. No parliament of religions can reconcile such fundamental and deep-rooted differences. We must conquer or be vanquished. In its origin, history, present attitude, and by the very first article of its brief creed, Islam is anti-Christian.[10]

Here again, the call to contextualization is robbing missions of its greatest weapon to reach Muslims, the fullness of God’s love for them as centered in the Trinity. Robert Letham explains: “The Trinity is a crucial element in outreach to Muslim people. It is often avoided because objections immediately arise. However, the implications of the Islamic view of Allah are far-reaching.” At its heart, Letham explains, love is something a person has for another person. He concludes: “Only a God who is triune can be personal. Only the Holy Trinity can love. Human love cannot possibly reflect the nature of God unless God is a Trinity of persons in union and communion.”[11] Muslims cannot experience the love of Allah, nor can they love Allah in return; all they can offer is their submission to Allah’s will. When the stakes are this high, dare we strip the Bible of its testimony to the triune God?[12]


There are other examples of where the Reformed faith serves the cause of Muslim evangelism most effectively. Zwemer has argued that the doctrine of total depravity addresses the functional Pelagianism in the Islamic doctrine of sin, and predestination offers an alternative to Islamic fatalism. This is not to claim that Reformed witnesses are alone wise in their approach to Muslim apologetics and evangelism. But we must not imagine that this is a “new threat” that demands new approaches, and we cannot abandon the rich resources of our tradition in the interest of theological trends that promise greater efficiency or claim to reduce the offense of the gospel.

Reflecting on Paul’s commendation of the “work of faith, labor of love and steadfastness of hope” of the Thessalonians (1 Thess. 1:3), Zwemer wrote: “How accurately these three short phrases depict the real task of carrying the good news to Muslims.”[13] “For thirteen long centuries,” he continued (and which we must now change to fourteen centuries),

whether by neglect or by the pioneer adventure of loyal hearts, this part of the non-Christian world has tested the faith of Christendom as by fire. It has demanded a measure of love utterly impossible except to those who had learned from Christ to love their enemies and his; and again and again Islam has deferred the fruition of hope and left for those who waited on and on, as their only anchor, the patience of unanswered prayer.[14]

As we engage with our growing number of Muslim neighbors in North America, the Reformed faith equips us to wait on the patience of God even as we anticipate the coming of his kingdom. Zwemer’s calls to faith, love, and hope in witness to the Islamic world find vivid expression in this prayer by the Apostle of Islam:

Almighty God, our Heavenly Father, who has made of one blood all nations and has promised that many shall come from the East and sit down with Abraham in your kingdom: We pray for your prodigal children in Muslim lands who are still afar off, that they may be brought near by the blood of Christ. Look upon them in pity, because they are ignorant of your truth.

Take away pride of intellect and blindness of heart, and reveal to them the surpassing beauty and power of your Son Jesus Christ. Convince them of their sin in rejecting the atonement of the only Savior. Give moral courage to those who love you, that they may boldly confess you name.

Hasten the day of religious freedom in Turkey, Arabia, Iran, Iraq, Afghanistan, and North Africa. Send forth reapers where the harvest is ripe, and faithful plowmen to break furrows in lands still neglected. May the tribes of Africa and Malaysia not fall prey to Islam but be won for Christ. Bless the ministry of healing in every hospital, and the ministry of love at every church and mission. May all Muslim children in mission schools be led to Christ and accept him as their personal Savior.

Strengthen converts, restore backsliders, and give all those who labor among Muslims the tenderness of Christ, so that bruised reeds may become pillars of his church, and smoking flaxwicks burning and shining lights. Make bare your arm, O God, and show your power. All our expectation is from you.

Father, the hour has come; glorify your Son in the Muslim world, and fulfill through him the prayer of Abraham your friend, “O, that Ishmael might live before thee.” For Jesus’ sake. Amen.


[1] Susan Jacobson. “New Mosque Highlights Growth of Muslim Community in Central Florida,” Orlando Sentinel, November 10, 2017, http://www.orlandosentinel.com/features/religion/religion-world/os-mosque-sanford-masjid-al-hajj-20171031-story.html.

[2] Bryan D. Estelle, “How Should the Reformed Church Respond to Islam?” Ordained Servant 17 (2008): 48–54, https://www.opc.org/OS/Ordained_Servant_2008.pdf#page=48.

[3] Samuel M. Zwemer, Islam and the Cross: Selections from “the Apostle to Islam,” ed. Roger S. Greenway (Phillipsburg, NJ: P&R, 2002).

[4] Samuel M. Zwemer, The Moslem Christ: an Essay on the Life, Character, and Teachings of Jesus Christ According to the Koran and Orthodox Tradition (Edinburgh: Oliphant, Anderson & Ferrier, 1912), 118.

[5] I have never found this quote in print, but I was told this by John Hesselink, former President of Western Theological Seminary (Holland, Mich.), who remembered Zwemer saying this frequently in addresses to college groups.

[6] Zwemer, Islam and the Cross, 32.

[7] Here as in other parts of the Qur’an Allah speaks to Muhammad in the first person plural. Readers should not conclude that this is an implicit expression of either Trinitarianism or polytheism. Rather, Allah is so high and exalted that the singular voice cannot always capture his magnificence.

[8] Zwemer, The Moslem Christ, 118.

[9] A very helpful critique of the Insider Movement is the 2014 study report of the PCA Ad Interim Study Committee on Insider Movements (SCIM), A Call to Faithful Witness, Part 2: Theology, Gospel Mission, and Insider Movements, http://pcahistory.org/pca/scim02_2014.pdf.

[10] Samuel M. Zwemer, The Moslem Doctrine of God: An Essay on the Character and Attributes of Allah According to the Koran and Orthodox Tradition (New York: Young People’s Missionary Movement, 1905), 119–20.

[11] Robert Letham, The Holy Trinity: In Scripture, History, Theology, and Worship (Phillipsburg, NJ: P&R, 2004), 443–44.

[12] Here again I would commend the PCA Study Committee on Insider Movements, in its 2012 report, A Call to Faithful Witness, Part 1: Like Father, Like Son: Divine Familial Language in Bible Translation, http://pcahistory.org/pca/scim01_2012.pdf.

[13] Zwemer, Islam and the Cross, 64.

[14] Ibid.

[15] Ibid., 153–54.

John R. Muether serves as a ruling elder at Reformation Orthodox Presbyterian Church, Oviedo, Florida, library director at Reformed Theological Seminary in Orlando, Florida, and historian of the Orthodox Presbyterian Church. Among the courses he teaches at Reformed Theological Seminary in Orlando is Christian Encounter with Islam. Ordained Servant Online, March 2018.

Publication Information

Contact the Editor: Gregory Edward Reynolds

Editorial address: Dr. Gregory Edward Reynolds,
827 Chestnut St.
Manchester, NH 03104-2522
Telephone: 603-668-3069

Electronic mail: reynolds.1@opc.org

Submissions, Style Guide, and Citations


Editorial Policies

Copyright information

Ordained Servant: March 2018

Islam Revisited

Also in this issue

Geerhardus Vos: Appreciation, Legacy, and Posthumous Publications

They Say We Are Infidels by Mindy Belz

The Myth of the Andalusian Paradise by Darío Fernández-Morera

The Jonathan Edwards Encyclopedia edited by Harry S. Stout

A New England Gentleman’s Epitaph

Download PDFDownload MobiDownload ePubArchive


+1 215 830 0900

Contact Form

Find a Church