The paper presents the following: 1) The factors which preceded the break of the unique Western Church (spiritual movements within the Roman Catholic Church, which requested a new kind of piety, a New-Century thought by most influential European humanists which was inspired by individualism, a changed political climate under the influence of the Humanism and Renaissance, the rise of the civil class and the invention of the printing press), 2) the founders of Protestant teachings (Martin Luther, Thomas Mincer, Philip Spener, Jean Calvin, Ulrich Zwingli) and 3) the rules of religious life among the newly converted (principles: Ecclesia reformata sed semper reformanda, Soli Deo Gloria, Solo Christo, Sola scriptura, Sola gratia, Sola fide, etc....