This article documents the evolution and survival of an institution that has persisted nearly two and a half millennia until the present day. This institution, the Mandæan calendar, has evolved since its origins in the early Hellenistic period, and has been faithfully maintained since 472 ce at the latest. Its essential structure, 12 equal months of 30 days extended with the addition of five days to maintain its correspondence with the passage of the seasons, has evidently not changed since its initial adoption. After introducing the basic elements of time-keeping among Mandæans today, the article addresses the system of days, months, years, eras, and ages employed in the Mandæan scriptures, and correlates them with the present Mandæan calendar as well as the Julian and Gregorian calendars.

Spoken vernacular dialects of Aramaic, generally known as Neo-Aramaic dialects, have survived down to modern times in various regions of the Middle East and can be divided into various subgroups. There are some islands of Neo-Aramaic in the West of Iran, which are situated on the eastern periphery of the Neo-Aramaic area. These include dialects spoken by Christians and Jews belonging to the North-Eastern Neo-Aramaic subgroup in the West Azerbaijan, Kordestan and Kermanshah provinces and Neo-Mandaic spoken by Mandaeans in the Khuzestan province. This paper examines a number of distinctive features of the Neo-Aramaic dialects of Iran, including those that have been induced by contact with other languages in the area.