As a catechist in Köthen he felt the lack of a good
catechism, and was encouraged by his superior, Johann Baptist Devis, to compose one. As a model he took the
Mainz catechism of 1842 and made use also of other textbooks, notably of
Bossuet's catechism. He completed his first catechism, called , in 1847. In 1848 it appeared anonymously at
Ratisbon and immediately won approval. Bishop Blum of
Linsburg introduced it officially into his
diocese the same year; the following year the bishops of
Trier and
Hildesheim did likewise for their dioceses. In 1850 the Bavarian bishops resolved to introduce a common catechism for the entire kingdom, and accepted Deharbe's catechism, which was then introduced in 1853. Other German dioceses adopted it as follows: •
Cologne, 1854 •
Mainz and
Paderborn, 1855 •
Fulda, 1858 •
Ermland, 1861 •
Culm, 1863 •
Gnesen-Posen, 1868 At the same time it spread outside of Germany, in Switzerland, Austria-Hungary, and the United States. It was translated in 1851 into Magyar, then into Bohemian, Italian, and French; into Swedish and Marathi, 1861; into Polish and Lithuanian, 1862; into Slovenian, 1868; into Danish, 1869; and later into Spanish and Portuguese. It was reintroduced into Bavaria in 1908. In a revised form, Austria adopted it in 1897. Deharbe himself prepared and published at Ratisbon four extracts of his first work, titled • (1847) (in English:
A Complete Catechism of the Catholic Religion) • (1847) • (1847) • (1849–50). He preserved catechetical tradition but abandoned the division of
Peter Canisius, arranging the text-matter under chapters on Faith, Commandments, and Means of Grace. His other works, all published at Ratisbon, are: • (1855) • (4 vols., 1857-64, fifth ed., (1880-) • (1865–68, sixth ed., Linden ed., 1898). ==References==