The Acathistus (from Greek, meaning “not [sung] sitting”), a Byzantine hymn to the Virgin Mary sung while standing, takes the form of an alphabetic acrostic and is thought to have been first composed by Romanus Melodus (6th cent.). The original served as a model for many similar hymns, especially in Russia. At times having considerable influence in the West, the Acathistus has been illustrated in picture-cycles since the 14th century.
A. Chadzinikolau, “Akathistos Hymnos,” RBK 1.94–96
G. Dévai, “Akathistos–Prooemia in …