(d after 1723). Organist and composer, active primarily in Germany. Of the Carmelite order, Father Justinus's name appears in Walther's Musicalisches Lexicon and Jacob Adlung's Anleitung zu der musikalischen Gelahrtheit. These citations refer to three didactic publications by Justinus, intended to teach various aspects of organ and harpsichord playing. Neither Walther nor Adlung identified Justinus's nationality, although if his first printed work appeared in Lentini, Sicily (as surmised by Eitner), perhaps he was of Sicilian or Italian origins. He was, according to Gerber, organist for his order in Würzburg between 1711 and 1723; subsequently he became organist for the Carmelite monastery at Abensberg, between Regensburg and Ingolstadt.
His three extant publications typify early 18th-century instruction manuals in which a brief set of rules is illustrated by music examples. Justinus explains the basic technical requirements of a keyboard player and devotes a few special observations to accompanying the ‘chorale’, i.e. the plainsong in the Catholic service, continuo realization, and the improvisation of fantasy pieces such as toccatas. The Musicalische Arbeith contains 13 Parthien or suites in four to 11 movements, each set to a different scale in the series C, c, D, d, E, e, E, F, g, G, a, A and B. The same collection also includes ten Ariae pastorellae, a Musette and a Soldaten-Marche with programmatic subtitles: ‘Musquet’, ‘Dragon’, ‘Courass’, ‘Hussar’, ‘Sipos oder Pfeiffer’. An appendix has a Sonata alla modern in one movement with four sections alternating slow–fast–slow–fast. Although Justinus's music is not without invention, it is generally of less interest in itself than as illustrations of the various keyboard practices which he describes in concise explanations.