The preaching of the Gospel to the poor, especially peasants, was the work at which he toiled unweariedly, till he was disabled by age. To this special work he bound himself and the members of the Congregation which he founded under the missionary Congregation of Secular Priests, by a perpetual vow approved by the Holy See. How great were his labours for bettering the discipline of the clergy, is attested by the building of Seminaries for the final education of young clerks, the number of meetings of Priests to discuss holy things, and the religious exercises preparatory to Ordination, for which, as well as for godly retreats by laymen, he wished that the houses belonging to his Institute should be always freely open. To spread wider the growth of faith and godliness, he sent his Gospel labourers not only into the several provinces of France, but also into Italy, Poland, Scotland, and Ireland, and also to Barbary and India. He assisted Louis XIII on his death-bed, and the Queen Anne of Austria, mother of Louis XIV, put him upon the young King's Council of Conscience during the Regency, in which position it was his unceasing effort that none but the most worthy should be named to churches and monasteries, that civil contests, duels, and creeping false doctrines, from which himself shrank as soon as he met them, should be put down, and that all men should yield the obedience which was due to the decisions of the Apostolic See.
There was no kind of misery which he did not strive with fatherly tenderness to relieve. Christians groaning in Mohammedan slavery, foundlings, deformed children, young maidens exposed to danger, houseless nuns, fallen women, convicts sent to the galleys, sick foreigners, disabled workmen, lunatics, and beggars without number, all these he relieved, and devoutly housed in divers charitable institutions which remain to this day. When Lorraine, Champagne, Picardy, and other districts were desolated by plague, famine, and war, he made immense efforts for their relief. He founded many charitable societies, to find out and succour the unfortunate. Among these are remarkable that of Matrons, and that of Sisters of Charity which hath been so widely spread. By those Of the Cross, Of Providence, and of St. Guinevere he aimed at bringing up young girls as school-mistresses. Amid all these and other most anxious business-matters, he remained always looking simply to God, kind to all, true to himself, plain, upright, and lowly. From all honours, riches, and pleasures, he ever shrank, and was heard to say, that nothing ever gave him any pleasure, except in Christ Jesus, whom it was his wish in all things to follow. With a body worn out with hardships, work and old age, he gently fell asleep in the house of St. Lazarus at Paris, the chief house of the Congregation of the Missions, upon the 27th day of September, in the year of salvation 1660, and of his own age the 85th. He was famous on account of his life, his works, and his miracles, and Clement XII inscribed his name among those of the Saints, appointing for his Feastday the 19th day of the month of July. Finally, at the earnest prayer of many prelates, Leo XIII proclaimed and established this hero of charity, illustrious for his services to all classes of men, as the patron before God in heaven of all charitable societies throughout the whole Catholic world which derive their origin in any way from his institution.