The Epistle of Eugnostos is one of many Gnostic tractates from the Nag Hammadi library, discovered in Egypt in 1945. The Nag Hammadi codices contain two full copies of this tractate. The epistle was a familiar literary convention of Antiquity; it is not to be supposed that this essay is an actual letter written by a man named Eugnostos ("right thinking", sometimes Eugnostus).
The text is devoid of any specifically Christian themes or associations, and simply describes the esoteric cosmology of the gnostics. The similarity with the cosmology in Sophia of Jesus Christ, led Douglas M. Parrott to conclude that that work was an adaption of this Epistle for a Christian audience. Parrott places the two side by side for comparison in his translation for The Nag Hammadi Library in English, edited by Robinson.