The Secret Book of John, also known as the Apocryphon of John, is a Gnostic text. In no other document of Gnostic literature is Gnostic mythology discussed so extensively. Nothing has ever been found of the original Greek text, but four manuscripts in Coptic are known. The first was found in 1896 and is part of the Codex Berolinensis. The other three were part of the discovery of the Nag Hammadi scriptures in 1945. These four manuscripts contain two different versions of the text. Two of the three manuscripts found at Nag Hammadi, NHC II.1 and NHC IV.1, contain textual parts not present in the other two versions. The latter two versions are therefore often referred to as the short recension, and the first two as the long recension. There are some minor differences between the two manuscripts of the long recension, but it is generally assumed within the field that both are based on the same Greek translation. However, the texts of the short recension show greater differences between them. These differences cannot be explained by assuming that they were translated independently of each other. The prevailing view in the field is that these must be translations of Greek texts that already differed from one another. Therefore, there must have been three different versions of the text in Greek. It is thus not possible to accurately reconstruct the oldest and most original text of the Apocryphon. There is a consensus in the field that the texts of the short recension must have originated earlier than those of the long recension. Since 1995, there has been a synoptic edition in which all four versions are visible side by side. The story of the Apocryphon is believed to have originated within the Gnostic tradition known as Sethianism.