He moved to Gotha to take up a post as chamber organist to the court in June 1686; he remained there for the rest of his life.
While on Witt's deathbed, Johann Sebastian Bach was commissioned to substitute for him and perform a Passiontide work for the court chapel (the Weimarer Passion BWV deest (BC D 1)).
His cantatas feature instrumental introductions, vocal concerto movements, solos, duets, homophonic chorale choruses, and are without recitatives.
Psalmodia sacra is an important hymnal from the late baroque; Marpurg wrote that it was the best he knew.
There are established chorale melodies by sixteenth and seventeenth century Thuringian composers along with over 100 new ones believed to have been written by Witt.