Calendars and the celebration of feasts and holidays form an important part of religious and national movements. Often they cause debate and lead to schism. It is well documented that the Qumran community followed a solar calendar which differed fundamentally from the lunar calendar observed at the Temple in Jerusalem. This volume contains texts composed by the Qumran community which delineated its calendar, considered 'God-ordained'. Some of the texts were written in a unique script known as 'Cryptic A' indicating their esoteric and secret nature.