He accepted the position in April 1594 , at the age of 23 .
Despite his desire to become a minister , near the end of his studies , Kepler was recommended for a position as teacher of mathematics and astronomy at the Protestant school in Graz .
Kepler accepted the position in April 1594 , at the age of 23 .
Despite his desire to become a minister , near the end of his studies , Kepler was recommended for a position as teacher of mathematics and astronomy at the Protestant school in Graz .