«SATIS COGNITUM». - Encyclical of Leone XIII (30 June 1896) on the unity of the Church (Acta Leonis XIII, XVI, Rome 1897, pp. 157-210; partially in Denz-U, 1954-62).
It opens by referring to the twofold error of those who deny the visibility of the Church by taking refuge in her supernatural character, or who consider her solely visible, as an ordinary institution, refusing her the character of regulator of divine communications. The Church, the Pontiff affirms, is a society at once external and internal, visible and invisible, human and divine (theandrism), like her exemplar and head, Gesù Cristo. This divine institution, to which every ecclesiological Nestorianism (mere visibility) and Monophysitism (mere invisibility) is repugnant, is, in imitation of Christ, whose continuation she is, “one,” and therefore possesses unity of faith (magisterium), worship (ministry), and rule (jurisdictional government). In order that the internal government of the Church might be endowed with perfect unity, Christ established the primacy of the Roman Pontiff, which neither destroys nor diminishes episcopal power, but unifies, defends, and strengthens II.
The encyclical illustrates, among other things, important points of ecclesiology: the intimate theandric structure of the Church, her unity, the magisterium and its necessity and importance, the Roman primacy and its relation to the episcopate.