  At the beginning of the academic year 1293/94 Eckhart held an inaugural lecture (Collatio in libros Sententiarum) that has been preserved. An academic sermon, the Sermo Paschalis a. 1294 Parisius habitus and the Tractatus super oratione dominica date from the same time. Between 1294 and 1298 Eckhart composed his Instructional Talks (Die rede der underscheidunge), table-talks for his confratres in the Erfurt monastery. From his first teaching period in Paris (1302/03) come the Quaestiones (Quaestio Parisiensis I, II and the rationes Equardi from one of the disputed questions of Gonsalvus Hispanus), as well as the Sermo die beati Augustini Parisius habitus, a feast-day sermon in honor of Augustine (August 18, 1302 or February 28, 1303), and perhaps two other Quaestiones. Between 1303 and 1310, during a General Chapter, Eckhart held the Sermones on Ecclesiastics 24: 23–27a and 24: 27b–31. In 1305 he began composing the Opus tripartitum, his major work, comprising three parts: the Opus propositionum (Work of Theses), with over 1,000 theses in 14 treatises, the Opus quaestionum (Work of Problems) and the Opus expositionum (Work of Interpretations).  Much of the Opus tripartitum remained incomplete. What we have are the Prologus generalis in opus tripartitum, the Prologus in opus propositionum, the Prologus in opus expositionum I and II, and various commentaries (above all the Expositio sancti evangelii secundum Iohannem).  Also preserved is an Opus sermonum containing drafts of Latin sermons. From the Strasbourg and Cologne period come the treatise Daz buoch der goetlîchen troestunge and the sermon Von dem edeln menschen. (The authenticity of the treatise Von abegescheidenheit has been disputed in the past, but it has been recently accepted once more as a work of Eckhart.) The most important German sermons also go back to this last period. Among these is Predigt 52, which due to its extremely innovative content was later translated from Middle High German into Latin.