Catholic communism in the context of "Rerum novarum"

Catholic social teaching (CST) is an area of Catholic doctrine which is concerned with human dignity and the common good in society. It addresses oppression, the role of the state, subsidiarity, social organization, social justice, and wealth distribution. CST's foundations are considered to have been laid by Pope Leo XIII's 1891 encyclical, Rerum novarum, of which interpretations gave rise to distributism (formulated by G. K. Chesterton), Catholic socialism (proposed by Andrew Collier) and Catholic communism, among others. Its roots can be traced to Catholic theologians such as Thomas Aquinas and Augustine of Hippo. CST is also derived from the Bible and cultures of the ancient Near East.

According to Pope John Paul II, the foundation of social justice "rests on the threefold cornerstones of human dignity, solidarity and subsidiarity". According to Pope Benedict XVI, its purpose "is simply to help purify reason and to contribute, here and now, to the acknowledgment and attainment of what is just ... [The church] has to play her part through rational argument and she has to reawaken the spiritual energy without which justice ... cannot prevail and prosper." Pope Francis, according to Cardinal Walter Kasper, made mercy "the key word of his pontificate... [while] Scholastic theology has neglected this topic and turned it into a mere subordinate theme of justice."

Rerum novarum, or Rights and Duties of Capital and Labor, is an encyclical issued by Pope Leo XIII on 15 May 1891. It is an open letter, passed to all Catholic patriarchs, primates, archbishops, and bishops, which addressed the condition of the working class. It discusses the relationships and mutual duties between labor and capital, as well as government and its citizens. Of primary concern is the need for poverty amelioration of the working class. It supports the rights of labor to form trade unions, and rejects socialism and laissez-faire capitalism, or unregulated, brutal capitalism, while affirming the right to private property and to a living wage.

A foundational text of modern Catholic social teaching, many of the positions in Rerum novarum are supplemented by later encyclicals, in particular Pius XI's Quadragesimo anno (1931), John XXIII's Mater et magistra (1961), Paul VI's Octogesima adveniens (1971), and John Paul II's Centesimus annus (1991), each of which commemorates an anniversary of the publication of Rerum novarum. It also inspired Catholic activism, and influenced distributists and supporters of corporatism. Socialists generally contest the encyclical's interpretation of socialism, and some socialists, particularly Catholic socialists, interpret Rerum novarum as not rejecting socialism, argue that divine law justifies the abolition of private property, and emphasize its anti-capitalist character.