Can the Church’s teaching on birth control change? During Pope Francis’ return flight from Canada, a journalist asked him about the possibility of a development in the Church’s teaching on contraception.

“This is very timely. But know that dogma, morality, is always in a path of development, but development in the same direction,” Pope Francis responded on July 30.

The pope went on to say that he thinks that the development of Catholic moral doctrine, in general, is fine but recommended in particular that it follows the rules outlined by the 5th-century theologian St. Vincent of Lérins.

Pope Francis explained that St. Vincent of Lérins taught “that true doctrine in order to go forward, to develop, must not be quiet, it develops ut annis consolidetur, dilatetur tempore, sublimetur aetate.”

“That is, it consolidates with time, it expands and consolidates, and becomes more steady, but is always ‘progressing.’ That is why the duty of theologians is research, theological reflection. You cannot do theology with a ‘no’ in front of it … the magisterium will be the one to say no,” the pope added.

Francis also addressed the recent controversy over a book published by the Vatican’s publishing house, which discussed “the possible legitimacy of contraception in certain cases.”

The book “Theological Ethics of Life: Scripture, Tradition, and Practical Challenges” was a 528-page synthesis of a theological seminar sponsored by the Pontifical Academy for Life in 2021.

Pope Francis said: “On the issue of contraception, I know there is a publication out on this issue and other marriage issues.”

“These are the proceedings of a congress and in a congress there are hypotheses, then they discuss among themselves and make proposals. We have to be clear: those who made this congress did their duty because they tried to move forward in doctrine, but in an ecclesial sense, not out, as I said with that rule of St. Vincent of Lerins.”

On the subject of birth control, the Catechism of the Catholic Church states that “legitimate intentions on the part of the spouses do not justify recourse to morally unacceptable means (for example, direct sterilization or contraception).”

St. Paul VI issued Humanae Vitae, the landmark encyclical reaffirming Church teaching against contraception, on July 25, 1968.

In the encyclical, Paul VI warned of serious social consequences if the widespread use of contraceptives became accepted. He predicted that it would lead to infidelity, the lowering of morality, a loss of respect for women, and the belief that humans have “unlimited dominion” over the body.

Pope Francis’ press conference on the papal plane touched on many topics, including his potential retirement and his response to the German “Synodal Way.” Pope Francis also described the forced removal of Indigenous children from their families and their treatment in Canada’s residential school system as a form of “cultural genocide.”

During his week-long journey to Canada, the pope traveled to Edmonton, Québec, and Iqaluit on what he called a “penitential pilgrimage” to apologize to the country’s indigenous communities.

Upon his arrival in Rome on Saturday morning, the pope went to Rome’s Basilica of St. Mary Major to spend a moment in prayer before an icon of the Blessed Virgin Mary.