In the first letter he strongly inculcates purity of morals, and warns all who professed the reformed religion against those irregularities of life, which were employed to the disparagement of their cause, by two classes of persons;――by the papists, who, although the same vices prevailed in a far higher degree among themselves, represented them as the native fruits of the reformed doctrine;――and by a new sect, who were enemies to superstition, but who had deserted the reformed communion, and were become scarcely less hostile to it than the papists. The principal design of this letter was to put his countrymen on their guard against the arts of this last class of persons and to expose their leading errors. {207} The persons to whom he referred went under the general name of anabaptists, a sect which sprung up soon after the commencement of the Reformation under Luther, and, breaking out into the greatest excesses, produced violent commotions in different parts of Germany. Being suppressed in the place of its birth, it spread through other countries, and secretly made converts by high pretensions to seriousness and Christian simplicity; the spirit of wild fanaticism, which at first characterised its disciples gradually subsiding after the first effervescence. Extravagancies of a similar kind have not unfrequently accompanied great revolutions; when the minds of men, released from the fetters of implicit obedience, and dazzled by a sudden illumination, have been disposed to fly to the extreme of anarchy and turbulence. Nothing proved more vexatious to the original reformers than this. It was urged by the defenders of the old system as a popular argument against all change. The extravagant opinions and disorderly practices of the new sect, though disowned and opposed by all sober protestants, were artfully imputed to them by their adversaries. And many who had declared themselves friendly to reform, alarmed, or pretending to be alarmed, at this hideous spectre, drew back, and sheltered themselves within the sacred pale of that church, which, notwithstanding her notorious dissensions, errors, and corruption, both in head and members, continued to arrogate to herself exclusively the properties of unity, universality, and perpetual infallibility.