The various Old Slavonic manuscripts are not the same but do appear to be derived from a common source. Many manuscripts are missing entire sections of chapters, and most are missing the final few chapters that focus on Methuselah, Nir, Melchizedek, and Noah. The collection of Old Slavonic manuscripts is generally divided into shorter and longer recensions. The various short recensions clearly share a common manuscript that served as an influence but are not simply copies of that manuscript as each has unique lines that were copied from longer recensions. The general conclusion of researchers is that the various short recensions were the works of various Orthodox Christian scholars. The longer recensions contain several Gnostic references, which implies the text may have originally been used in Slavic lands by the Bogomil Gnostic-Christians who were common in the Balkans between the 12th and 14th centuries. Nevertheless, the Gnostic sections of the text do not appear to have been written by the Slavs and were almost certainly in the Greek manuscript by the 9th century AD.