The first Christians weren't Bible Christians

[Aractus]

Someone here pointed me to a book by Hyam Maccoby on Paul as mythologizer, the true inventor of Christianity (and quite the opportunist and liar). Maccoby makes, inter many alia, the interesting observation that if Paul was really a Pharisee trained by Gamaliel he'd not have used the LXX. In some of the letters (those agreed not pseudonymous) he used LXX phrases that differ from their Hebrew counterparts, so that the Hebrew text was not his source. I can't recall them, and finding the specific cites would require drudgery.

Well he didn't use the LXX, he used the proto-lxx, we do not know what it was prior to the Hexapla's fifth column. Also he used scribes, his scribes probably couldn't read Hebrew?

Aractus, if the Protestants did all that noble restoration, why do so many of their translations still have Isaiah 7:14 so wrong, and so very few have it right?

Well I'm glad you asked. Why? Because of this:

• Isaiah 7:14 LXX: Therefore the Lord himself shall give you a sign; behold, a virgin shall conceive in the womb, and shall bring forth a son, and thou shalt call his name Emmanuel.
  Isaiah 7:14 MT/DSS: Therefore the Lord himself will give you a sign. Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel.
  Matthew 1:23: “Behold, the virgin shall conceive and bear a son, and they shall call his name Immanuel”

Matthew never quotes from the LXX(/proto-lxx), he in fact is quoting from the Hebrew just like Luke and I could go through all of his quotes and prove it if I had to. Here's another:

• Matthew 2:17-18
  Then was fulfilled what was spoken by the prophet Jeremiah:
  
  “A voice was heard in Ramah,
  weeping and loud lamentation,
  Rachel weeping for her children;
  she refused to be comforted, because they are no more.”
  
  Jeremiah 31:15
  Thus says the Lord:
  “A voice is heard in Ramah,
  lamentation and bitter weeping.
  Rachel is weeping for her children;
  she refuses to be comforted for her children,
  because they are no more.”
  
  Jeremiah 38:15 (LXX)
  A voice was heard in Rama, of lamentation, and of weeping, and wailing; Rachel would not cease weeping for her children, because they are not.

So the question for you would be actually why do both Matthew and the LXX translate as "virgin" independently of each other?