Which conditions must be met for the decisions of an ecumenical council to be considered infallible?

For the decisions of an ecumenical council to be considered infallible, it is crucial that the bishops are gathered with the specific intent to define matters of faith or morals in communion with the pope's authority. This reflects the understanding that for infallibility to be claimed, the assembly must not only consist of bishops but must also include the necessary theological foundation of intent and alignment with the papal authority.

Infallibility in this context is tied to the belief that the Magisterium (the teaching authority of the Church) is guided by the Holy Spirit when defining doctrines pertaining to faith and morals. This ensures that the declarations are not merely the result of a majority consensus but are rooted in a divine assurance of correctness that is recognized by the Church. This emphasizes the importance of both the intent of the bishops and the necessity of cooperation with the pope, who serves as the successor of Saint Peter, the rock upon which the Church is built.

Other options do not fully capture the theological and hierarchical structure necessary for infallibility. For instance, holding a council in Rome is not a requisite for infallibility; rather, it is the intention and alignment in faith matters with the pope that play a critical role. Similarly, a majority vote among bishops