Mission of Divine Mercy: The U.S. Sedevacantist Group Whose Superior Has Been Excommunicated by the Bishop of San Antonio
Archbishop Gustavo Garcia‑Siller of San Antonio declared automatic excommunication of Father John Mary Foster for refusing to submit to the Pope. Foster heads the Mission of Divine Mercy, a sedevacantist group considered schismatic by the diocese. The excommunication removes Foster from clerical state, preventing him from celebrating sacraments or exercising jurisdiction. The decision follows a tribunal that began in April 2025 and concluded with the bishop’s public statement. The action underscores the diocese’s stance against schismatic movements within the Catholic Church.
about 1 month ago
The Archbishop of San Antonio, Gustavo Garcia‑Siller, announced the automatic (latae sententiae) excommunication and dismissal from the clerical state of Father John Mary Foster, leader of the Mission of Divine Mercy, for schism after a tribunal found him guilty of refusing to submit to the Pope — first Francis and now Leo XIV — and continuing to celebrate Mass in defiance of diocesan directives. 1
The Mission of Divine Mercy was founded by Foster in 2010 and operated as a private association of the faithful approved by the Archdiocese of San Antonio. In March 2024 the archbishop withdrew its ecclesiastical approval, suppressed its statutes, and removed Foster’s priestly faculties after the group began publishing alleged private revelations despite a bishop‑imposed ban. 1
Foster claimed to receive prophetic messages from God, the Virgin Mary, and the Holy Spirit, urging a “great battle” against a corrupt Church hierarchy. He publicly labeled Pope Francis and his successor, Pope Leo XIV, as “usurpers,” and continued to celebrate Mass without mentioning the Pope in the Eucharistic Prayer, directly violating the archbishop’s orders. 1
An ecclesiastical tribunal, authorized by the Holy See, opened proceedings in April 2025 and issued a guilty verdict on April 20, 2025. The archbishop’s August 14, 2026 notification declared Foster’s automatic excommunication and barred Catholics in the diocese from attending or supporting his activities, emphasizing that participation would constitute a formal act of disobedience. 1
Garcia‑Siller urged the faithful to guard their hearts against Foster’s influence, to refrain from financial or material support, and to pray for Foster’s reconciliation, noting that the canonical penalties aim at healing rather than punishment. 1
Foster and his followers continue to reject both Pope Francis and Pope Leo XIV, asserting that the 2025 conclave was invalid because many cardinals were appointed by Francis. They have not appealed the excommunication, claiming there is no legitimate authority to which they can turn. 1
Excommunication illustrates Catholic Church’s stance against sedevacantism
Excommunication illustrates the Catholic Church’s opposition to sedevacantism because it defends communion with the Roman Pontiff and rejects the private claim that the pope has lost or never possessed the papal office. However, the cited documents address schismatic acts and rejection of papal authority more directly than sedevacantism as a distinct movement.
Catholic teaching regards unity with the pope as essential to the visible unity of the Church. In Ecclesia Dei, Pope John Paul II judged the unauthorized episcopal consecrations carried out by Archbishop Marcel Lefebvre to be:
“an act of disobedience to the Roman Pontiff in a very grave matter,” which “implies in practice the rejection of the Roman primacy” and “constitutes a schismatic act.”
This principle directly contradicts sedevacantism. Sedevacantism does not merely criticize a pope’s prudential decisions; it denies that the current occupant is truly pope. Such a position attacks the Church’s visible structure and the role of the successor of Peter as the principle of unity.
Pope Benedict XVI explained that excommunication was imposed on the four bishops consecrated in 1988 because the consecrations endangered the unity of the College of Bishops with the pope. He stated that the Church employed excommunication:
“with the aim of calling those thus punished to repent and to return to unity.”
The remission of the penalty had the same purpose: reconciliation and restoration of communion. Therefore, excommunication is not intended simply to condemn a person permanently. It is a disciplinary remedy calling the offender back to the Church’s unity.
This is important when addressing sedevacantists. The Church’s response should combine clarity concerning the error with charity toward persons, inviting them to reconsider their judgment and return to full communion.
The Church also rejects the idea that Catholic doctrine becomes binding only when it satisfies an individual’s interpretation of tradition, the opinions of theologians, or a preferred reading of a council. Benedict XVI insisted that the Church’s teaching authority cannot be “frozen” in a particular historical period and that authentic Catholic faith includes the whole doctrinal history of the Church.
Likewise, John Paul II called Catholics to fidelity to Tradition as it is authentically interpreted by the ecclesiastical Magisterium, including the ecumenical councils from Nicaea through Vatican II. He warned against “erroneous interpretations and arbitrary and unauthorized applications” in doctrine, liturgy, and discipline.
Sedevacantism commonly arises when individuals make their own theological judgment the final standard for determining whether a pope is legitimate. Catholic ecclesiology, however, does not give private individuals authority to depose a pope or declare the Holy See vacant.
The Dicastery for the Doctrine of the Faith reiterated in 2026 that episcopal consecrations without the required papal mandate constitute a “schismatic act,” and that formal adherence to schism entails excommunication under Church law.
A subsequent decree declared that certain unauthorized consecrations incurred latae sententiae excommunication—an automatic penalty attached to the completed offense—and warned clergy and laity not to adhere to the schism because they too could incur the penalty.
These measures demonstrate that the Church continues to regard rejection of papal authority and separation from ecclesial communion as gravely contrary to Catholic faith and discipline.
It would be imprecise to say that every person who criticizes a pope is automatically a sedevacantist or automatically excommunicated. The Church distinguishes between:
Excommunication concerns a canonical offense and requires the conditions established by Church law. The 2003 Holy See decision, for example, distinguished between latae sententiae penalties, incurred automatically by the commission of a delict, and ferendae sententiae penalties, imposed after a formal process.
Thus, the canonical status of a particular person cannot be determined merely from labels or internet statements.
Excommunication illustrates the Church’s stance against sedevacantism indirectly but decisively. It shows that communion with the Roman Pontiff, recognition of his authority, and rejection of self-appointed separation are essential elements of Catholic unity. The penalty is medicinal: it seeks repentance, reconciliation, and return to full communion rather than permanent exclusion. Consequently, sedevacantism is incompatible with Catholic ecclesiology because it replaces the Church’s visible, apostolic communion with a private judgment about the papal office.