Ascension
In his text Against Heresies, Irenaeus tells about the Gnostic view that the Ascension happened eighteen months after the Resurrection. The apocryphal text known as the Apocryphon of James describes the teachings of Jesus to James and Peter 550 days after the resurrection, but before the ascension. This text suggests an even longer period. The recently discovered Nag Hammadi Gospel of Thomas, like the canonical Gospel of Matthew, does not mention the Ascension.