Historically, Protestant views on the Roman Mass, particularly during the Reformation, were sharply critical. Reformers like Martin Luther, John Calvin, and Huldrych Zwingli rejected the Roman doctrine of transubstantiation. They viewed the Mass as unbiblical, often criticizing it as a “resacrifice” of Christ, which they argued contradicted the once-for-all sacrifice described in Hebrews 10.¹ These views were codified in Reformation-era confessions and led to centuries of Catholic-Protestant enmity, with the Mass often at the center of theological disputes.

These theological differences remain significant. Since the Second Vatican Council (1962–65), however, ecumenical dialogues have softened Catholic-Protestant relations. A 2024 Christianity Today article highlights a trend of evangelicals converting to Roman Catholicism or Eastern Orthodoxy, partly due to appreciation for the “deeper reverence of liturgy and the sacraments,” including the Eucharist.² This seems to suggest that some evangelicals find the Roman Mass appealing, even if they do not fully embrace its theology.

A 2024 America Magazine article proposes that Roman Catholics and Protestants partake in their respective Eucharistic rites side by side, signifying a growing openness to shared worship services, even if doctrinal differences remain. The author, a Protestant, expresses respect for the Roman Eucharist as a “profound and sacred mystery,” suggesting a shift away from the historical Protestant posture of condemnation of the Roman Mass as an unbiblical atrocity.³

Anecdotally, I can recall numerous conversations that I have had with Protestants in recent years—even folks who are otherwise ostensibly Reformed—who have admitted to attending Roman Mass and appreciating its reverence, even if they do not accept transubstantiation. Some former Protestants converting to Roman Catholicism cite the Eucharist’s centrality as a draw, which suggests a positive shift among a subset of evangelicals regarding the doctrine and practice of the Roman Church. In fact, a 2024 Catholic Answers article recounts a conversation where an evangelical expresses indifference to the Roman view of the Eucharist, suggesting that it is “not a big deal” despite theological differences.⁴This indifference, while not a full-on endorsement of the legitimacy of the Roman Mass, marks a significant departure from historical Protestant hostility toward it.

What are we to make of this seemingly casual indifference to the Roman Mass among some modern-day Protestants? Would our Reformed and Protestant forebears address the vast doctrinal and theological chasm that exists between the two traditions as “not a big deal,” analyzing the divergence with barely a shrug?

Hardly.

While confessional Protestants often turn to notable luminaries such as Luther or Calvin in order to find windows into classical Protestant attitudes regarding Romanism and the Mass, today I would like to turn to a less frequently consulted figure, John Knox. Though not as prolific in his theological writings as men like Luther and Calvin, the Reformer and so-called Father of Scottish Presbyterianism’s writings on the matter are instructive and illuminating when it comes to discerning classical Protestant views towards Rome and her Mass.

In order to distill Knox’s views on the matter, we will consult both Knox’s “Vindication of the Doctrine that the Sacrifice of Mass is Idolatry” (1550)⁵ and “A Summary, According to The Holy Scriptures, of the Sacrament of The Lord’s Supper” (1550).⁶ For the purposes of this and at least one subsequent article, the greatest benefit of Knox’s “Vindication” is that it provides a more comprehensive window into Knox’s own sacramental theology. Knox’s smaller treatise, “A Summary,” also provides a clear insight into Knox’s thought on the doctrine, but the “Vindication” is a more thoroughgoing treatment of the larger eucharistic-doctrinal issues of the day. The larger treatise offers a broader analysis of the pressing pastoral concerns for the church as Knox understood them.

Knox Against the Mass

In his “Vindication,” Knox expresses what a difficult thing it is to dislodge a long-standing, ingrained doctrine such as the Mass from the esteem of the people. By this point in history, a centuries-long understanding had developed within the Roman Church that the Eucharist, or the Mass, occupied a central, if not the most central, point in Rome’s religious system.⁷ In the midst of the Protestant Reformation, Knox and others arduously labored to dissuade people of this notion.⁸ He compares such a task as not unlike that of the apostle Paul trying to dislodge the affection of the goddess Diana from the culture of the Ephesians.⁹ He regards the practices of the Mass as no different from the vain offerings of the pagan nations,¹⁰ and no less offensive to God than the blasphemous, inventive worship and illegitimate sacrifices put forth by scriptural figures such as King Saul or Nadab and Abihu.¹¹ Believing that because Jesus Christ alone is king of his church and, as such, alone has the right to institute its ordinances, Knox argues that the Roman Church errs to the point of blasphemy by both inventing and then mandating the Sacrifice of the Mass. He contends that much of the ceremonial Mass was not instituted by either Christ or the apostles in the early days of the church, but was gradually expanded and supplemented, layer by layer, down through the ages by figures such as Pope Gregory.¹² He observes how, centuries later, Boniface commanded the altars to be covered in clean cloths, Gregory the Great commanded the candles to be lit at the gospel readings during the service, and Pontianus commanded the Confiteor to be uttered at the outset of the service.¹³

Though Roman Church apologists would allege that St. Peter said the first Mass, Knox rejoins that the Mass in all its liturgical fullness (as Rome by then mandated) did not solidify until hundreds of years after Peter’s death.¹⁴ Although Rome would argue that their specified ceremonial applications through the years are akin to the instructions handed down by the Jerusalem Council,¹⁵ Knox demonstrates how the apostles appealed to Scripture in rendering their decision and did not spuriously create doctrine: the Jerusalem Council offered further case-specific instruction on the basis of previous Scripture, not novel liturgical customs suited for the moment.¹⁶

Knox asserts that the Lord’s Supper is a perpetual memory of the benefits that Christians have already received from Jesus Christ via his once-for-all sacrifice and death. Conversely, the Mass is instituted to be a perpetual sacrifice for the sins of those both living and dead,¹⁷ an ongoing, memorial sacrifice for sins wherein Christ is offered, in body and blood, as an appeasement unto the Father.¹⁸ Knox fiercely asserts: “The Mass is no sacrifice for sin. . . . Only the blood of Christ taketh away our sins. . . for if full admission stood not in him alone, then they that eat him yet hungered and they drank him yet thirsted; and that were contrary to his own words. . . . Consider now, Brethren, if the opinion of the Mass be not vain, false, and deceivable?”¹⁹

Conclusion

In short, for Knox, the Roman Mass is a wholly different entity than the biblical sacrament of the Lord’s Supper, and the doctrine of the Mass is wholly at odds with the doctrine communicated by the Supper.²⁰ Understanding this distinction is key not only for Knox’s sacramentology but for his pastoral theology. For Knox, it is crucial that God’s people, whether civic leaders or common parishioners, come away with this biblical and doctrinal understanding.

Having given some consideration to Knox’s vehement opposition to the Roman Mass, we will return in our next article to give some attention to Knox’s positive articulation of the doctrine of the Lord’s Supper and some pastoral implications thereof.

Notes

1. Diarmaid MacCulloch, The Reformation: A History (New York: Viking Penguin, 2004), 134–140, 159–162.
2. Andrew Voigt, “Some Evangelicals Are Leaving Protestantism for Other Traditions,” Christianity Today, August 13, 2024.
3. Meg Giordano, “A call for Catholics and Protestants to receive Communion—side by side,” America Magazine, November 7, 2024.
4. Carl Olson, “A Eucharistic Potluck with Protestants,” Catholic Answers, November 18, 2024.
5. Knox, “A Vindication of the Doctrine that the Sacrifice of Mass is Idolatry,” in The Works of John Knox (Edinburgh: Banner of Truth, 2015), 3:33–70.
6. Knox, “A Summary, According to The Holy Scriptures, of the Sacrament of The Lord’s Supper,” in Works of John Knox (Edinburgh: Banner of Truth, 2015), 3:71–75.
7. It is beyond the purview of this article to engage in this much broader discussion. Admittedly, there is some disagreement as to whether this has always been the theology of Rome or whether this was a de novo doctrine articulated in the twentieth century at the Second Vatican Council in its Dogmatic Constitution on the Church (Lumen Gentium) and Constitution on the Sacred Liturgy (Sacrosanctum Concilium). For Knox, at least, it was certainly his perception of Rome’s self-understanding of the doctrine: “I know that in the Mass hath not only been esteemed great holiness and honoring of God, but also the ground and foundation of our religion. So that, in opinion of many, the Mass taken away, there resteth no true worshipping nor honouring of God in the earth. The deeper hath it pierced the hearts of men, that it occupies the place of the last and mystical Supper of our Lord Jesus.” Works, 3:34.
8. Knox, “A Vindication of the Doctrine,” Works, 3:33.
9. Cf. Acts 19.
10. Knox, “A Vindication of the Doctrine,” Works, 3:34.
11. Knox, “A Vindication of the Doctrine,” Works, 3:35, 37.
12. Knox, “A Vindication of the Doctrine,” Works, 3:38.
13. The General Confession in the Ordinary of the Mass that begins “Confiteor Deo omnipotenti, beatæ Mariæ semper Virgini, beato Michaeli Archangelo,” etc. (“I confess to Almighty God, to blessed Mary ever Virgin, to blessed Michael the Archangel. . .”).
14. Knox, “A Vindication of the Doctrine,” Works, 3:48.
15. Cf. Acts 15.
16. Knox, “A Vindication of the Doctrine,” Works, 3:42–46.
17. Knox, “A Vindication of the Doctrine,” Works, 3:48.
18. Knox, “A Vindication of the Doctrine,” Works, 3:57.
19. Knox, “A Vindication of the Doctrine,” Works, 3:61.
20. Knox, “A Vindication of the Doctrine,” Works, 3:64.

©Sean Morris. All Rights Reserved.

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Post authored by:

• Sean Morris

  

  Sean was educated at Grove City College, Reformed Theological Seminary (Jackson, MS), Edinburgh Theological Seminary, and the University of Glasgow (Scotland). He earned his PhD from Puritan Reformed Theological Seminary. He is an ordained teaching elder in the Presbyterian Church in America, and serves as a minister at the Covenant Presbyterian Church in Oak Ridge, TN. He also serves as the Academic Dean of the Blue Ridge Institute for Theological Education and has published numerous theological and devotional articles. Sean lives in Oak Ridge with his wife, Sarah, and their children.

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