lo, the Savior appeared, after departing from us while we gazed after him. And
five hundred and fifty days since he had risen from the dead, we said to him, "Have you departed and removed yourself from us?" But Jesus said, "No, but I shall go to the place from whence I came. If you wish to come with me, come!"
They all answered and said, "If you bid us, we come."
http://www.gnosis.org/naghamm/jam.html
Is this understanding (Gnostic text) 'biblical' or would it be considered 'extra-biblical'?
How would this understanding confirm the Mormon gospel in regards to Jesus appearing in America, and who in America at that time would have confirmed his appearance? According to what pre-Columbian texts? Is there any evidence of these appearances?