From 1805 to 1820, Bernard Bolzano was professor of religious doctrine (Religionslehre) at the University of Prague. The lectures he had to deliver were part of the so-called Philosophical Studies that every student of the university had to complete before he entered the higher studies, i.e. the studies of medicine, law or theology. As professor of religious doctrine, Bolzano also had the duty to deliver the homilies on Sundays and holidays during the academic year to all the students of the Philosophical Studies. This explains the enormous influence Bolzano exerted through these homilies on the intellectual and political life of Bohemia in his time, whose offshoots reached even the Charta 77 movement in former Czechoslovakia. The chairs of religious doctrine were established by the Austrian emperor Franz at all universities of the Austrian empire in order to shape the students into good Christians and law-abiding citizens as it was ordered in a decree. The homilies Bolzano had to deliver at the University of Prague (as did all professors of religious doctrine at Austrian universities) were called Erbauungsreden (edifying addresses) or exhortations. There is evidence for 582 Erbauungsreden Bolzano delivered as a professor at the University of Prague of which 414 are extant; of these, 153 have not yet been published at all. The 414 Erbauungsreden that are extant have survived in different form: some of them (70) as autographs, i.e. in Bolzano's own handwriting, others in handwritten copies of Bolzano's manuscripts, others in notes taken by Bolzano's students. Several collections of Bolzano's Erbauungsreden have already appeared in print, some of them during Bolzano's lifetime, while others were published posthumously by his students or other editors. - The new critical edition of Bolzano's Erbauungsreden presents all of them in chronological order. Those which are extant will be edited on the basis of the best version which has remained. Those Erbauungsreden which are not extant will be documented and described according to an index Bolzano himself has prepared.Bolzano held more edification speeches in the academic year 1809/1810 that in any other year in which he was teaching. During this time he held 52 of these speeches. Six speeches have been preserved as autographs, there are only notes for four of the speeches, and only the dates are known for two of the speeches. Most of the others are still in existence as transcripts reproduced in facsimile. In the edification speeches held in the academic year 1809/1810, Bolzano's concept of education, which includes the entire personality, is shown especially clearly. There are twice as many speeches which have a generally advisory content than there are speeches which deal mainly with religious issues. In keinem anderen Jahr seiner Lehrtatigkeit hat Bolzano so viele Erbauungsreden gehalten wie im Studienjahr 1809/1810, in dem er es auf 52 brachte. Sechs Reden sind als Autographen erhalten; von vier Reden haben wir nur Notizen, von zwei ist nur das Datum bekannt. Alle anderen sind grossteils mehrfach in orignalgetreuen Abschriften uberliefert. - In den Erbauungsreden des Studienjahres 1809/1810 wird Bolzanos Erziehungskonzept, das die gesamte Personlichkeit umfasst, besonders deutlich. Den Reden, die hauptsachlich religiose Fragen behandeln, stehen doppelt so viele Reden allgemein beratenden Inhalts gegenuber.