Sometimes known as the Harp of the Holy Spirit, Saint Ephrem the Syrian was a prolific hymnographer and theologian of the 4th century CE. According to some accounts, his father was a pagan priest. Ephrem, however, converted Syria to Christianity. He taught and composed at Nisibis and Edessa until his death in 373. His writings have been widely influential, and he is venerated by both the Eastern churches and Rome. He is also notable for conducting choirs that consisted entirely of whom? Discuss