Mater et Magistra & Pacem in Terris: Peace on Earth and Good Will Towards Men

From the invaluable Compendium of the Social Doctrine of the Church. Excerpts:

...Blessed Pope John XXIII, in his Encyclical Mater et Magistra[164], “aims at up-dating the already known documents, and at taking a further step forward in the process of involving the whole Christian community”[165]. The key words in the Encyclical are community and socialization[166]: the Church is called in truth, justice and love to cooperate in building with all men and women an authentic communion. In this way economic growth will not be limited to satisfying men's needs, but it will also promote their dignity.

With the Encyclical Pacem in Terris[167], Blessed Pope John XXIII brings to the forefront the problem of peace in an era marked by nuclear proliferation. Moreover, Pacem in Terris contains one of the first in-depth reflections on rights on the part of the Church; it is the Encyclical of peace and human dignity. It continues and completes the discussion presented in Mater et Magistra, and, continuing in the direction indicated by Pope Leo XIII, it emphasizes the importance of the cooperation of all men and women. It is the first time that a Church document is addressed also to “all men of good will”[168], who are called to a great task: “to establish with truth, justice, love and freedom new methods of relationships in human society”[169]. Pacem in Terris dwells on the public authority of the world community, called to “tackle and solve problems of an economic, social, political or cultural character which are posed by the universal common good”[170]. On the tenth anniversary of Pacem in Terris, Cardinal Maurice Roy, the President of the Pontifical Commission for Justice and Peace, sent Pope Paul VI a letter together with a document with a series of reflections on the different possibilities afforded by the teaching contained in Pope John XXIII's Encyclical for shedding light on the new problems connected with the promotion of peace[171]...(articles 94-95)