abstract:Cyrillus, Greek jurist of the 5th century, was a professor in the ancient Law School of Berytus (present-day Beirut), and one of the founders of the oecumenical school of jurists (τῆς οἰκουμένης διδάσκαλοι). This school preceded the succession of Anastasius to the Eastern empire (AD 491), and paved the way for Justinian's legislation.