Here, in 1562, one of the first productions in Germany of the morality play Homulus (corresponding to the English Everyman or the Dutch Elckerlijc) was given in Latin by the students under his direction.
From Munich, where he was succeeded in 1565 by the celebrated Paul Hoffaeus, he was transferred to Dillingen, where for twenty years he presided over the college and the academy and laboured with zeal and success for the improvement of studies and for the religious training of the students.
In company with his distinguished brother, he attended the first provincial congregation of the Society of Jesus in Upper Germany, and furthered important reforms in the teaching of philosophy.
In 1585 he was made rector of the Jesuit College of Ingolstadt, and in this capacity became a member of the German commission which tested in practice the first draft of the Ratio Studiorum.
A fortnight after his arrival the death of St. Peter Canisius was announced; the shock deprived Theodorich of memory and speech, an affliction which he bore with exemplary patience for seven years.