The chief occupation of the church for the last three centuries was the maintenance of that authority conferred by Christ on S. Peter and his successors, in opposition to the efforts of Protestantism for its overthrow; and the contest was terminated for ever in the dogmatic definition of Papal Infallibility, by the church assembled in council in the Vatican. Luther declared the pope Antichrist. The Catholic Church affirmed the pope to be the Vicar of Christ. Luther stigmatized the See of Rome as the seat of error. The council of the church defined the See of Rome, the chair of S. Peter, to be the infallible interpreter of divinely-revealed truth. This definition closed the controversy. In this pressing necessity of defending the papal authority of the church, the society of S. Ignatius was born. It was no longer the refutation of the errors of the Waldenses and the Albigenses that was required, nor were the dangers to be combated such as arise from a wealthy and luxurious society. The former had been met and overcome by the Dominicans; the latter by the children of S. Francis. But new and strange errors arose, and alarming threats from an entirely different quarter were heard. Fearful blows were aimed and struck against the keystone of the divine constitution of the church, and millions of her children were in open revolt. In this great crisis, as in previous ones, Providence supplied new men and new weapons to meet the new perils. S. Ignatius, filled with faith and animated with heroic zeal, came to the rescue, and formed an army of men devoted to the service of the church, and specially suited to encounter its peculiar dangers. The Papacy was their point of attack; the members of his society must be the champions of the pope, his body-guard. The papal authority was denied; the children of S. Ignatius must make a special vow of obedience to the Holy Father. The prevailing sin of the time was disobedience; the members of his company must aim at becoming the perfect models of the virtue of obedience, men whose will should never conflict with the authority of the church, _perinde cadaver_. The distinguishing traits of a perfect Jesuit formed the antithesis of a thorough Protestant. The society founded by S. Ignatius undertook a heavy and an heroic task, one in its nature most unpopular, and requiring above all on the part of its members an entire abnegation of that which men hold dearest--their own will. It is no wonder that their army of martyrs is so numerous and their list of saints so long.