In 1808 he published his _Reflections on the Position of the Church in France_, a work which was suppressed by Napoleon's government. He greeted the returning Bourbons with enthusiasm. But he was not yet famous. Between 1817 and 1823, however, there was published, volume by volume, a work which kept men's minds in a constant ferment, and gave occasion to violent controversy; between the publication of the second and third volumes its author had to take up his pen in his own defence. This work was the Abbé de la Mennais' _Essai sur l'indifférence en matière de religion_. In it the period of the restoration of ecclesiasticism collects all its powers for a last, decisive battle. We find all the leading principles of the day enunciated with a peremptoriness and a determined consistency in the drawing of conclusions which seem to indicate that the revulsion is at hand. The tendency and even the title of this book suggest comparison with the work which inaugurated the religious revival in Germany in the beginning of the nineteenth century, Schleiermacher's famous _Reden über die Religion an die Gebildeten unter ihren Verächtern_ (Lectures upon Religion to the Educated amongst those who despise it). Both works aim at counteracting the same thing, the indifference towards religion, the positive contempt for it, prevailing amongst the educated classes. Both make an attempt, now that faith has become weak, to rebuild the edifice of piety upon a new foundation. It is in this attempt that the different nationality of the authors makes itself strongly felt.