Codex Tchacos is an ancient Egyptian Coptic codex from approximately 300 AD, which contains early Christian gnostic texts: the Letter of Peter to Philip, the First Apocalypse of James, the Gospel of Judas, and a fragment of The Temptation of Allogenes (a different text from the previously known Nag Hammadi Library text Allogenes).
Codex Tchacos is important because it contains the first known surviving copy of the Gospel of Judas, a text that was rejected as heresy by the early Christian church and lost for 1700 years. The Gospel of Judas was mentioned and summarized by the Church Father Irenaeus of Lyons in his work Against Heresies.[1] This would date the Gospel of Judas to some time prior to Irenaeus' writing, and therefore older than the codex itself.