"and "Vita veterum sapientium" (both 1637); others, such as "Jordanssteine" (1636) challenge orthodox Lutheranism or, as in "Oculus siderius", discuss astronomical questions.He had a reputation as an insightful teacher, and the crux of his teachings was the unity with God based on the denial of all things worldly and of the self; particular emphasis was placed on the significance of Christ for the attainment of salvation.