One of the canonical books of the Old Testament.

an Old Testament book consisting of reflections on the vanity of human life; is traditionally attributed to Solomon but probably was written about 250 BC

Hebrew qoheleth, he who calls together an assembly; member of an ecclesia; a book of the Old Testament written by King Solomon (Septuagint). An ecclesiastic is a clergyman. Ecclesiastical is of the church or the clergy, used in early Latin and Greek writings about Christianity.