Roellig, the quintessential example of a musician in courtly service, performed and composed music principally for use in the Schloßkirche.
The St Mark Passion (1750) and later vocal works, such as the coronation music for Gustav III of Sweden (1772) and the only published work, the motet Lobe den Herrn (1785), indicate a style that is very similar to that adopted by his almost exact contemporaries Gottfried August Homilius (1714-1785) and Johann Friedrich Doles (1715-1797).
Works such as the St. Mark's Passion „Gehet heraus und schauet an, ihr Tochter Zion" (1750), previously attributed to C. P. E. Bach, indicate the quality of his writing.
In 2019, the local newspaper, the Volksstimme reported that a volume had been bought for the Francisceum Library in Zerbst which contained the texts of several unknown works by Fasch and Roellig.
Significant surviving works include Roellig's cantata to mark the death of Adolf Frederick, King of Sweden in 1771 (RISM 190013945 "Sei getreu bis in den Tod") and a cantata (RISM 190022943 "Euer Herz soll sich freuen") and Missa brevis to mark the coronation of his successor Gustav III.