Catholic-Protestant Differences (Part 1)

by on October 8, 2025 | Comment

I began my teaching career at Gordon-Conwell Theological Seminary. Most of my students elected to attend that seminary; it was not the denominational seminary of any denomination, so choosing to attend there was a choice not to attend a particular denomination’s favored/sponsored seminary. Many, if not most, of my students there were “denominationally fluid,” as it were, curious to discover which aspect of the Christian heritage was their own. This denominational openness, however, was not absolute. Gordon-Conwell Seminary was and is an “evangelical” institution, in the older sense of the term to denote “Protestant.”1 Few students who attended Gordon-Conwell considered converting to Roman Catholicism.2

The last two thirds of my teaching career were at Grove City College, where, on average, 15% of the student body was Roman Catholic. Nearly every year, I had conversations with students who were considering converting to Catholicism or to Protestantism, and I regarded it as my duty as an academic to assist them in thinking well about the matter (though, to my recollection, none ever did think well about the matter). I attempted, unsuccessfully, to suggest that the matter was not to be undertaken lightly, nor, especially, was it to be undertaken merely out of a recent dissatisfaction about their then-present ecclesiastical circumstance. Rather, I suggested that there were at least a dozen differences of a substantial nature between the two traditions, and that an individual should not “convert” from one tradition to the other merely on the basis of one or two of those differences. If an individual is 80% Catholic, he should probably remain Catholic, and if another individual is 80% Protestant, he should probably remain Protestant.

In one Protestant-Catholic dialogue at Franciscan University in Steubenville, Ohio, I recalled most of the items below from memory during the Q&A Session, and Dr. Alan Schreck (himself Roman Catholic) read a nearly identical list from a book he had written. He wryly observed: “Dr. Gordon and I disagree on a dozen matters; but we agree about the dozen matters about which we disagree.” The list below is my (and Dr. Schreck’s) baker’s dozen of matters that I routinely suggested for the consideration of those thinking about converting. Sadly, I do not recall a single individual who considered all of them before converting in either direction. In fact, if my now-feeble memory serves me well, I do not recall a single individual considering even as many as three of the dozen. I suppose the late Peter L. Berger was right when he observed that, for most churchgoers, religion is not an intelligent concern.3 If religion were to become an intelligent concern for some individuals, the following list might be recommended for their consideration. I will present the list first without comment, and then will comment briefly about several of them for those who may be less familiar with the particular beliefs or practices.

  1. Sale of Indulgences
  2. Pope as the Head of the Visible Church
  3. Transubstantiation
  4. Mass as a Sacrifice
  5. Seven Sacraments or Two Sacraments
  6. Purgatory
  7. Use of Images in Public Worship
  8. Justification by Faith Alone
  9. Infallible Magisterium
  10. Tradition Equal to Scripture
  11. Infrequent Communion (once annually before the Reformation, and only in one kind; now Catholics practice frequent communion, and many Protestants practice infrequent communion)
  12. Ex Opere Operato Efficacy of the Sacraments
  13. Latin Mass (changed at Vatican II in 1963)4

1. Sale of Indulgences

To my knowledge, the sale of indulgences is no longer practiced, but never, to my knowledge, has it been repudiated. The sale of indulgences was the sole subject of Luther’s 95 Theses; historically, this—and the Catholic reaction to it—was the incident that ignited the Reformation.

What is an indulgence? Here is an answer from “Catholic Answers” (hereafter CA):

But in the special sense in which it is here considered, an indulgence is a remission of the temporal punishment due to sin, the guilt of which has been forgiven. . . . It is not an exemption from any law or duty, and much less from the obligation consequent on certain kinds of sin, e.g., restitution; on the contrary, it means a more complete payment of the debt which the sinner owes to God. . . . Least of all is an indulgence the purchase of a pardon which secures the buyer’s salvation or releases the soul of another from Purgatory.5

There are (at least) two major problems with the sale of indulgences: what an indulgence is, and whether such could be bought or sold via money. Protestants do not (universally or consistently) believe that there are “temporal punishment(s) due to sin,” which we take to be a distinctive feature of the Mosaic covenant, in which (Deut 27) the twelve tribes stand and hear twelve curses that will come upon them if they sin in particular ways:

Cursed be the man who makes a carved or cast metal image . . . dishonors his father or his mother . . . moves his neighbor’s landmark . . .  misleads a blind man on the road . . . perverts the justice due to the sojourner, the fatherless, and the widow . . . lies with his father’s wife . . .  lies with any kind of animal . . . lies with his sister . . .  lies with his mother-in-law . . . strikes down his neighbor in secret . . . takes a bribe to shed innocent blood . . .  does not confirm the words of this law by doing them. (Deut 27:15–26)

After each of these twelve curses, “all the people” answered and said, “Amen,” solemnly taking upon themselves these threatened curses.

Most Protestants (again, perhaps not universally or consistently) believe what Paul said in Galatians 3:13, “Christ redeemed us from the curse of the law by becoming a curse for us,” especially since he just two verses before had cited Deuteronomy 27:26, the final of the twelve curses that Moses had administered. He also referred not to the curses of the law (in the plural), but to the curse of the law (in the singular), addressing the entire cursing dimension of the Sinai covenant as a singular reality from which Christ “redeemed/paid for our release.” Protestants do not believe that there remains, in the new covenant, “temporal punishment due to sin” (although all sin deserves punishment). Protestants do not believe that there is “a more complete payment of the debt which the sinner owes to God” than the payment Christ made on the cross. Further, Protestants do not believe that Christ redeemed us from some, many, or even most of the Mosaic curses, but from the entirety of them (and from the Adamic cursing also). We refer to Christ as “the only Redeemer of God’s elect” (Westminster Shorter Catechism 21), not to him as “the major redeemer of God’s elect.” The notion that you, I, monks, nuns, or any others could redeem us from temporal punishments due to sin (even if such temporal punishments remained as part of our covenant) would make them co-redeemers with Christ.

Secondly, another offensive aspect of the sale of indulgences is that the church would make money by selling to people relief from their sense of guilt. Protestants call all such activity “Simony,” after the Samarian magician who attempted to purchase from the apostles the power to give the Holy Spirit to others (Acts 8:9–24). To prey upon fearful consciences and extract money from them (used, in large part, to pay for the construction of St. Peter’s Cathedral in Rome) is perceived by Protestantism as contrary to him who said, “Freely you have received; freely give” (Matt 10:8).

Notes

  1. The German language still ordinarily employs the term evangelische to mean “Protestant;” and Die Evangelische Kirche in Deutschland has almost twenty-million members.
  2. A notable exception may have been Scott Hahn, who graduated from GCTS in 1982, and converted to Catholicism in 1986. My tenure there began in 1984, so I did not know Scott as a student. He now teaches at Franciscan University in Steubenville, Ohio, only about an hour away from me, and we occasionally see each other; I regard him as a friend and always enjoy our conversations.
  3. Dr. Peter L. Berger (1929–2017) was a sociologist and theologian, who spent the latter decades of his career at Boston University (he earlier taught at Rutgers and the New School for Social Research). He focused on the Sociology of Knowledge and the Sociology of Religion, and was persuaded that such sociological factors were far more influential than intellectual factors for most people. A similar thesis is promoted by Dr. Alan Jacobs (Baylor) in his How to Think: A Survival Guide for a World at Odds (Currency, 2017), especially chapter 3, “Repulsions,” in which he discusses “the repugnant cultural other,” as a category that influences our beliefs negatively.
  4. In his spiritual autobiography, Nearer My God, William F. Buckley Jr. objected to the vernacular mass, and objected to women not being priests; oddly, he nevertheless continued to believe in an infallible magisterium.
  5. Catholic Answers, s.v. “Indulgences,” accessed August 22, 2025, https://www.catholic.com/encyclopedia/indulgences. In the interests of fairness, I will ordinarily permit Catholic sources to describe Catholic practices and beliefs.

©T. David Gordon. All Rights Reserved.

You can find this whole series here.

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    Dr. T. David Gordon is a teaching elder in The Presbytery of the Ascension. Before retirement, he taught at Gordon-Conwell Seminary (1984–98) and Grove City College (1999–2021).

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