It has been six decades since St. John XXIII wrote the encyclical "Pacem in Terris” (“Peace on Earth”), but Pope Francis stands by its message and says it is still relevant in today’s world.

“60 years ago, St. John XXIII addressed the encyclical "Pacem in Terris" to the Church and to the world,” Pope Francis said in a recent tweet. “I invite everyone to read it, because it is more timely than ever. And I pray that the heads of nations might allow it to inspire projects and decisions.” 

John XXIII was called upon as an intermediary when President John F. Kennedy and Soviet leader Nikita Khrushchev faced off and were on the brink of war during the Cuban Missile Crisis in 1962. Serving as pope at the time, John XXIII encouraged dialogue to resolve the crisis. 

Upon reflecting on his work during the crisis, John XXIII conceived the "Pacem in Terris” encyclical. He considered it would serve as a prophetic message of peace to the world's superpowers. The encyclical, a response to the dangers of the Cold War, expanded upon his approach. It emphasized the need for dialogue and cooperation between nations to promote peace, America Magazine said in an article. 

"Pacem in Terris" did not focus on nuclear arms or other subjects that often come to mind when considering Catholic teachings on peace and war. Rather, it put forward ideas that could build a framework of peace that was based on the acknowledgment, reverence, protection and advancement of human rights. This approach established the direction for the Church's involvement in global affairs in the following years, America Magazine added.

The encyclical has since played a key role in Catholic social teaching as it was the first document highlighting human rights as a fundamental aspect of its framework. The Vatican shared the content of "Pacem in Terris." It addresses teachings on the Order Between Men, Rights, Rights Pertaining to Moral and Cultural Values, the Right to Worship God According to One's Conscience, the Right to Choose Freely One's State in Life, Economic Rights and more.