The basilica of Saint Paul Outside the Walls in Rome. Image by Hervé Simon, CC-BY-SA 2.0, here.
On Sunday, January 25, 2026, Antipope Prevost (“Leo XIV”) has delivered an address in the Basilica of St. Paul Outside the Walls on the occasion of the “Prayer Week for Christian Unity”. There were representatives of Orthodox and Protestant denominations present.
We need to consider what the Church always understood under the word “unity”. The Church has always taught that “unity” has three aspects: unity of doctrine (unity of faith), unity of worship and unity of government.
For example, the Catechism of St. Pius X taught:
“[The Ninth Article of the Creed] 14 Q. Why is the Church called One?
A. The true Church is called One, because her children of all ages and places are united together in the same faith, in the same worship, in the same law; and in participation of the same Sacraments, under the same visible Head, the Roman Pontiff.”
Let’s look at a current example.
Do Catholics and Protestants have the same faith?
Obviously not. Protestants don’t believe in the papacy, in the Assumption of Mary, etc. I might add that Protestants don’t have the same faith among each other: Baptists claim that children can’t be baptized, other Protestants baptize children; Lutherans believe that Christ is present in the bread and the wine, while others treat them as only symbols etc.
Do Catholics and Protestants have the same worship?
Obviously not. The main form of Catholic worship is the Holy Mass. At Holy Mass, through the ministry the priest, the sacrifice of Calvary is renewed in an unbloody manner, and the bread and the wine become the real Body and Blood of Christ. Protestants go to a Sunday service, where there is no Eucharist.
Do Catholics and Protestants have unity of government, that is, do they recognize the same Church authorities, especially the pope?
We know the answer.
If someone would object that I am schismatic, rejecting the unity of government, since I don’t recognize Robert Prevost as a legitimate pope, I respond: I recognize all the popes from St. Peter until Pius XII. These real popes have left us ways to recognize who can’t be popes: heretics for example. Paul IV has left us his bull Cum ex apostolatus officio, in which he declared that if someone has been elected pope and it comes to light that he was a heretic before his election, the election is invalid and any layperson has the right to recognize that. In other words: it is Robert Prevost and the others before him, who broke with the unity of faith.
What is interesting is that “Leo XIV” can be compared on this matter with Leo XIII. In fact, Pope Leo XIII wrote an entire encyclical on the unity of the Church, called “Satis Cognitum”. I am going to quote a few passages.
“Indeed no true and perfect human society can be conceived which is not governed by some supreme authority. Christ therefore must have given to His Church a supreme authority to which all Christians must render obedience. For this reason, as the unity of the faith is of necessity required for the unity of the church, inasmuch as it is the body of the faithful, so also for this same unity, inasmuch as the Church is a divinely constituted society, unity of government, which effects and involves unity of communion, is necessary jure divino. ‘The unity of the Church is manifested in the mutual connection or communication of its members, and likewise in the relation of all the members of the Church to one head’ (St. Thomas, 2a 2ae, 9, xxxix., a. I).” (Satis cognitum 10)
“Jesus Christ, therefore, appointed Peter to be that head of the Church; and He also determined that the authority instituted in perpetuity for the salvation of all should be inherited by His successors, in whom the same permanent authority of Peter himself should continue. And so He made that remarkable promise to Peter and to no one else: “Thou are Peter, and upon this rock I will build my church” (Matt. xvi., 18). “To Peter the Lord spoke: to one, therefore, that He might establish unity upon one” (S. Pacianus ad Sempronium, Ep. iii., n. 11).” (Satis cognitum 11)
“These things enable us to see the heavenly ideal, and the divine exemplar, of the constitution of the Christian commonwealth, namely: When the Divine founder decreed that the Church should be one in faith, in government, and in communion, He chose Peter and his successors as the principle and centre, as it were, of this unity. Wherefore St. Cyprian says: “The following is a short and easy proof of the faith. The Lord saith to Peter: ‘I say to thee thou art Peter’; on him alone He buildeth His Church; and although after His Resurrection He gives a similar power to all the Apostles and says: ‘As the Father hath sent me,’ &c., still in order to make the necessary unity clear, by His own authority He laid down the source of that unity as beginning from one” (De Unit. Eccl., n. 4). And Optatus of Milevis says: “You cannot deny that you know that in the city of Rome the Episcopal chair was first conferred on Peter. In this Peter, the head of all the Apostles (hence his name Cephas), has sat; in which chair alone unity was to be preserved for all, lest any of the other apostles should claim anything as exclusively his own. So much so, that he who would place another chair against that one chair, would be a schismatic and a sinner” (De Schism. Donat., lib. ii).” (Satis cognitum 15)
Prevost began his speech by talking about Saint Paul the Apostle. The start of the speech is not special: He describes the life and the conversion of Paul accurately.
In his speech Prevost refers to “[m]y dear predecessor, Pope Francis” and to “my venerable predecessor Saint John Paul II”. Why not to any popes before the council?
“In the passage from the Letter to the Ephesians chosen as the theme for this year’s Week of Prayer, we repeatedly hear the adjective “one”: one body, one Spirit, one hope, one Lord, one faith, one baptism, one God (cf. Eph 4:4-6). Dear brothers and sisters, how can these inspired words not touch us deeply? How can our hearts not burn within us when we hear them?”
Leo XIII had this to say in Satis cognitum on the same Bible passage from Ephesians:
“The need of this divinely instituted means for the preservation of unity, about which we speak is urged by St. Paul in his epistle to the Ephesians. In this he first admonishes them to preserve with every care concord of minds: “Solicitous to keep the unity of the Spirit in the bond of peace” (Eph. iv., 3, et seq.). And as souls cannot be perfectly united in charity unless minds agree in faith, he wishes all to hold the same faith: “One Lord, one faith,” and this so perfectly one as to prevent all danger of error: “that henceforth we be no more children, tossed to and fro, and carried about with every wind of doctrine by the wickedness of men, by cunning craftiness, by which they lie in wait to deceive” (Eph. iv., 14): and this he teaches is to be observed, not for a time only-“but until we all meet in the unity of faith…unto the measure of the age of the fulness [sic] of Christ” (13). But, in what has Christ placed the primary principle, and the means of preserving this unity? In that-“He gave some Apostles-and other some pastors and doctors, for the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ” (11-12).” (Satis cognitum 9)
Yes, there is one Baptism: the Sacrament of Baptism, which washes away sin and makes one a member of the Catholic Church. There is one faith, the Catholic Faith. Pius XII wrote in Humani Generis that revelation teaches “that the Mystical Body of Christ and the Roman Catholic Church are one and the same thing.” (Humani generis 27)
Prevost then claims:
“We are one! We already are! Let us recognize it, experience it and make it visible!”
How can that even be? According to one commentator, when when Pope Saint Pius X called Modernism the “synthesis of all heresies” in his landmark encyclical Pascendi, people couldn’t imagine how literal it could become.
In his speech, Prevost also mentions the Council of Nicaea in 325. In the year 325, neither Protestantism nor Orthodoxy existed. Instead, there were heresies such as Arianism, which the council dealt with.
All participating bishops in the Council of Nicaea were Catholic. They examined the teachings of Arius, and condemned them. If they would’ve taken Prevost’s approach, they wouldn’t have condemned anyone and instead organized an ecumenical prayer service with the Arians.
“As we look toward the 2,000th anniversary of the Passion, Death and Resurrection of the Lord Jesus in 2033, let us commit ourselves to further developing ecumenical synodal practices and to sharing with one another who we are, what we do and what we teach (cf. Francis, For a Synodal Church, 24 November 2024, 137-138).”
Let’s pray to God that the Catholic Church be restored by the 2000th anniversary of the Redemption.
I would like to add that the Catechism of the St. Pius X explains the first petition of the Our Father like this:
“11 Q. What do we ask in the First Petition when we say: Hallowed be Thy Name?
A. In the First Petition: Hallowed be Thy Name, we ask that God may be known, loved, honored and served by the whole world and by ourselves in particular.