The Ginza Rabba, Ginza Rba, or Sidra Rabba, and formerly the Codex Nasaraeus, is the longest and the most important holy scripture of Mandaeism.

Mandaeism, sometimes also known as Nasoraeanism or Sabianism, is a Gnostic, monotheistic and ethnic religion with Greek, Iranian, and Jewish influences. Its adherents, the Mandaeans, revere Adam, Abel, Seth, Enos, Noah, Shem, Aram, and especially John the Baptist. Mandaeans consider Adam, Seth, Noah, Shem and John the Baptist prophets, with Adam being the founder of the religion and John being the greatest and final prophet.