Shawnb said
14:51 And there followed him a certain young man, having a linen cloth cast about his naked body; and the young men laid hold of him: 52 And he left the linen cloth, and fled from them naked.

Since Jesus was in charge of proceedure, before the Roman guard arrived at Gethsemane, instructing the disciples to stay awake etc. , he would have been involved with this naked boy, identified as ‘a certain young man,’ ‘certain’ meaning they knew him, and he ‘followed him,’ he followed Jesus, in some sort of ritual. Morton Smith contends that raising the dead rituals involve fasting and  nudity. Jesus himself is soon to be resurrected from the dead, not the same as raising, but a related ritual. Perhaps this was a ritual preparation. The Secret Gospel of Mark and bibles of other apocalyptic preachers give these rituals in more detail.

The fact that the bible says Jesus is the only son of God, instead of just the son of God, tells us the Gospel spoke to an audience who knew there were other sons of God. Preachers, or buddhas, at the time used the title son of God, the Son, or a variety of other titles. They came, a lot them from Egypt, which had about a million population of Jews and practiced a more meditation style of Judaism. Judaism had two centers with two temples, one in Jerusalem and one in Cairo. Baigent writes about this in The Jesus Papers.

Morton Smith contends that versions of Mark and screeds began to be written right after the crucifiction, that Mark is not from oral traditions as Bart claims. He thinks three versions of Mark existed before our Greek version, one a secret one containing the rituals which were forbidden by the Roman’s. Also since it was normal for these apocalyptic preachers to write their own bibles, and therefore a possibility Jesus wrote a bible, now lost. Our knowledge of these times is sketchy. Morton Smith claims the literacy rate was thirty percent, much higher than Barts claim.  

Wikipedia

The gospel is mentioned exclusively in the Mar Saba letter, a document of disputed authenticity, which is said to be written by Clement of Alexandria (c. AD 150–215).

The Mar Saba letter is addressed to one Theodore (Greek: Θεόδωρος, Theodoros), who seems to have asked if there is a gospel of Mark in which the words “naked man with naked man” (Greek: γυμνὸς γυμνῷ, gymnos gymnō) and “other things” are present. Clement confirms that Mark wrote a second, longer, mystic and more spiritual version of his gospel, and that this gospel was “very securely kept” in the Alexandrian church, but that it contained no such words. Clement accuses the heterodox teacher Carpocrates for having obtained a copy by deceit and then polluted it with “utterly shameless lies”. To refute the teachings of the gnostic sect of Carpocratians, known for their sexual libertarianism, and to show that these words were absent in the true Secret Gospel of Mark, Clement quoted two passages from it.

There were accordingly three versions of Mark known to Clement, Original Mark, Secret Mark, and Carpocratian Mark. The Secret Gospel of Mark is described as a second “more spiritual” version of the Gospel of Mark composed by the evangelist himself. The name derives from Smith’s translation of the phrase “mystikon euangelion”. However, Clement simply refers to the gospel as written by Mark. To distinguish between the longer and shorter versions of Mark’s gospel, he twice refers to the non-canonical gospel as a “mystikon euangelion” (either a secret gospel whose existence was concealed or a mystic gospel “pertaining to the mysteries” with concealed meanings), in the same way as he refers to it as “a more spiritual gospel”. “To Clement, both versions were the Gospel of Mark”. The purpose of the gospel was supposedly to encourage knowledge (gnosis) among more advanced Christians, and it is said to have been in use in liturgies in Alexandria.