Throughout history, the Catholic Church has turned to Ecumenical Councils and the Magisterium to define its doctrine, resolve theological crises, and establish disciplinary norms. Ecumenical councils, in particular, are solemn gatherings of bishops from around the world, convened by the Pope to address questions of great importance. These councils have played a crucial role in shaping the Church’s doctrinal identity and in clarifying the most complex aspects of Christian theology.
4.5.1 Ecumenical Councils: Defining the Faith and Resolving Heresies
To date, the Church has held 21 Ecumenical Councils, each responding to the challenges of its time. The first of these, the Council of Nicaea (AD 325), was convened to resolve the Arian controversy, which denied the divinity of Christ. The Nicene Creed, which affirms that Jesus is ‘true God from true God, begotten, not made, of the same nature as the Father,’ remains one of the principal professions of faith of Christians around the world.
Other councils, such as the Council of Trent (1545–1563), were held in response to the Protestant Reformation and clearly defined Catholic doctrine on the sacraments, justification, and the Eucharist, reaffirming the authority of the Pope and the importance of tradition alongside Scripture. The Council of Trent also reformed ecclesiastical discipline, establishing seminaries for the formation of the clergy and promoting catechesis to counter Protestant teachings.
The Second Vatican Council (1962–1965) marked a significant change in the Church’s history, since it was convened not to resolve a specific heresy but to ‘open the windows of the Church’ and adapt it to the realities of the modern world. Vatican II documents, such as ‘Lumen Gentium’ and ‘Gaudium et Spes,’ redefined the Church’s relationship with the contemporary world, emphasizing the collegiality of bishops, the active participation of the laity, and commitment to interreligious dialogue.
Each council has left a lasting mark on the Church’s doctrine, liturgy, and pastoral practice. Although councils may provoke internal tensions and debates, their aim is always to preserve the unity and purity of the faith. The teachings of ecumenical councils possess the highest doctrinal authority and are regarded as infallible when they concern matters of faith and morals.
4.5.2 The Ordinary and Extraordinary Magisterium: The Voice of the Church
The Church’s Magisterium is the Church’s teaching authority, exercised by the Pope and the bishops in communion with him. This magisterium may be ordinary (everyday teachings expressed through encyclicals, pastoral letters, and addresses) or extraordinary (solemn definitions of doctrine through councils or the Pope’s ex cathedra declarations).
The ordinary Magisterium is expressed in documents such as encyclicals and apostolic exhortations. Examples include Pope Paul VI’s encyclical ‘Humanae Vitae’ (1968), which reaffirmed the prohibition on the use of artificial contraceptives, and John Paul II’s encyclical ‘Fides et Ratio’ (1998), which defended the compatibility of faith and reason. These teachings are binding on Catholics, although they do not possess the same degree of immunity from error as the solemn definitions of the extraordinary magisterium.
The extraordinary magisterium is exercised in a special way when the Pope defines a doctrine as infallible by virtue of his authority as Peter’s successor. The most recent case was the proclamation of the dogma of the Assumption of the Virgin Mary in 1950 by Pope Pius XII, who affirmed that the Virgin was ‘assumed into heaven in body and soul.’ These definitions are considered definitive and cannot be changed.
The challenge for the magisterium is to find a balance between faithfulness to tradition and openness to a new understanding of the faith in light of the signs of the times. In this regard, Pope Francis has emphasized that pastoral discernment is essential, since it makes it possible to apply the Church’s teachings to concrete situations in a way that respects both truth and mercy.
4.5.3 The Church and Infallibility: What It Means and When It Applies
The concept of infallibility has often been misunderstood, both inside and outside the Church. Papal infallibility, formally defined at the First Vatican Council (1869–1870), refers to the Pope’s ability to proclaim, ex cathedra, a doctrine of faith or morals as definitive. However, this infallibility is exercised very rarely and under specific conditions.
Infallibility does not mean that the Pope cannot make mistakes in his personal life or in his opinions on temporal matters. It applies only when, as supreme pastor, he defines a teaching that must be believed by all the faithful. Infallibility may also be exercised by an ecumenical council when all the bishops, in communion with the Pope, define a truth as belonging to the deposit of faith.
The purpose of infallibility is to protect the Church from doctrinal errors and ensure that the faith handed on is the same apostolic faith received from Christ and the apostles. This ensures that, throughout the centuries, the Church maintains unity in fundamental teachings, even when faced with new theological or moral challenges.
