2 The present Encyclical is part of these celebrations, which are meant to thank God — the origin of "every good endowment and every perfect gift" (Jas 1:17) — for having used a document published a century ago by the See of Peter to achieve so much good and to radiate so much light in the Church and in the world. Although the commemoration at hand is meant to honour Rerum novarum, it also honours those Encyclicals and other documents of my Predecessors which have helped to make Pope Leo's Encyclical present and alive in history, thus constituting what would come to be called the Church's "social doctrine", "social teaching" or even "social magisterium". The validity of this teaching has already been pointed out in two Encyclicals published during my Pontificate: Laborem exercens on human work, and Sollicitudo rei socialis on current problems regarding the development of individuals and peoples.
Source: Centesimus Annus (Vatican.va)