In a newsgroup exchange, the follwing (indented) statements were, brought by a Muslim to support the validity of the Gospel of Barnabas. My answer follows up immediately after each point.

   1. Iranaeus who lived 130 - 200 AD acknowledges Gospel of Barnabas in his
      writings. In fact he uses it to argue his monotheism versus the Trinity
      doctorine introduced by St Paul.

Please give exact quotation and reference. I am virtually certain 
that you are wrong.    http://wesley.nnc.edu/noncanon/fathers.htm
gives you the writings of the church fathers, including Irenaeus. 
I couldn't find a "gospel of Barnabas" in any of those files. 
The works by Irenaeus are also available at 
http://ccel.wheaton.edu/fathers2/ANF-01/TOC.htm

Let me know when you found the passage you claim to exist.

   2. In 383 AD the Pope secured a copy of Gospel of Barnabas for his own Library.
      Fra Marino was a friend of Pop Sixtus (1585 - 1590) found the Gospel of Barnabas
      in the library of Pope. 

Fallacy of fallacies. That is from the preface of the Gospel of 
Barnabas as far as I remember. Obviously, when the work itself is a 
forgery you don't ask the forgerer what story he likes to make up 
to give it the air of credibility. The above is NOT historical fact, 
but part of the whole scheme.


                               It was translated ito Italian. The Italian version
       finally was presented in 1713 AD to Prince Eugene of Savoy by J. E. Cramer 
       who was a Councilloe of the King of Prussia.

   3. It was acquired by Hofbibliothek in Vienna in 1738 AD.

That is about right, but the fact that this forgery passes from one
person to the next does not thereby increase its authenticity. 

   4. Toland's posthumous work published in 1747 AD has a list of forbidden Gospels
      according to the Glasian Decree of 496 AD. The Gospel of Barnabas is on that
      list.

This might be correct, but we know nothing at all about the content
of this gospel. And the internal and external evidence of the text
you refer to proves that it is a forgery from the 13th century at
the earliest. Therefore it can hardly be the book mentioned in the
Gelasian Decree. This should be obvious. It might be, though, that
"Fra Marino" took the Gelasian Decree and the fact that nothing 
was known of this "Gospel of Barnabas" as the occasion to write his 
gospel under this name and therefore give it the appearance of being
connected to something ancient. This however has to remain speculation.

   5. The Oxford University Press published an English translation (by Ragg) of the
      Gospel of Barnabas in 1907. This book was removed from circulation by folks who
      considered it un-fit to be read. However a copy exists in British Museum and one
      in the Library of Congress.

Another wild and false claim. ... I did a library search, and found 
14 libraries in the US and 5 in Europe which have this original edition
on their shelves. Let alone the many libraries which have several other 
reprint editions of a later date. 

Sadly, some people all too easily believe what they are told by their 
party propagandists.  But let me ask you a question too. 

Why do you think that the many Islamic publishers who reprint 
the text of this pseudo-gospel do NOT include the introduction
and critical discussion of it, that was in the original edition
you refered to in the above? That is an interesting question,
don't you think so? I am looking forward to your response.
Please do NOT ignore this question.

   There are other data. However the objective is to demonstrate to the readers
   that they need to look beyond attempts to casually dismiss this Gospel by
   Barnabas.  These and other data do not support the fabrication that the Muslims
   somehow conspired to introduce the Gospel of Barnabas to confuse Christians.

They certainly very much so support it. Actually, I don't _necessarily_
say that it was written by Muslims, but it certainly was written in order
to get the favor of the Muslims and to support the Islamic understanding.

   It is a far more convincing and coherent presentation of Christianity as 
   preached by Jesus, narrated by someone who was an eye-witness: versus what 
   St Paul insists on despite the fact that he never met Jesus in his life.

The Gospel of Barnabas was written IN ORDER TO support Islamic theology.
No wonder you find it more in harmony with it. The writer has achieved
his purpose. But what does that prove?

If you favorite color is green, and you find something green, does that
mean the particular thing should be green as its authentic color? If that
green thing happens to be cheese, then this means it has gone moldy and
is ready to be thrown away, no matter how pleasing the color is to your
eyes. You are interpreting your personal preference as evidence for 
authenticity and truth. Certainly not a scientific approach. 

I hope I answered your arguments to your satisfaction and you 
are now better prepared to carefully think about the reasons  
why scholars have unanimously judged this work to be a 
forgery from the middle ages. 

Another Muslim responded also to my scepticism:

    > Yes, Muhammad is mentioned in it, but it was after all constructed
    > for that very reason. This "gospel" is in quite unanimous opinion
    > of the scholars a medieval forgery.
  
    It is not a uanimous opinion of th scholars as Katz would like to push the
    case. There are many scholars who believe that it is not a medieval Muslim
    forgery. Check e.g., the following site:
   
       http://ironbark.bendigo.latrobe.edu.au/~blackhir/Entry.html

I wrote "medieval forgery" (see the last two words of mine that you 
quoted above). Where do you see me state that it is done by a Muslim?

You need to read more careful. Some scholars believe it might have
been done by a Muslim, some others do not believe so. But they DO
agree that it is a MEDIEVAL forgery, including Prof. Blackhirst whose 
website you are refering to. Will you accept his verdict that it
is from the middle ages and hence not an authentic gospel? If yes,
why then would you even want to defend it, instead of warning the
Muslims to use a fraud to bolster their case for Islam?

In particular, Dr. Blackhirst says on this page in his second 
paragraph:

  ... it is clearly a work of the Middle Ages. It purports to be 
  the 'True Gospel' of Jesus and is very obviously adapted to 
  Muslim purposes...

    What if one 'Western' scholar is quoted who says that it is not a
    medieval Islamic forgery? Very likely Katz will quickly change his tune.

Again, read before you attack. I didn't say ISLAMIC forgery even though 
you twice tried to make it look like I did. I only said MEDIEVAL FORGERY 
and your reference confirmed it nicely. Thank you very much.

This particular Muslim then responded again:

   There is a difference between verdict and opinion. Blackhirst opinion
   cannot become verdict unless a solid evidence is shown. 

He is one of very few scholars today who does any work on this 
book. But let me ask again. Do you know of ANY scholar (I mean 
_scholar_, not Muslim propagandist) who holds the Gospel of 
Barnabas to be authentic and who has published this conviction 
in an academic journal or a book in an academic publishing house? 

I do not know of even one. You are setting yourself not only 
against the majority of scholarship to side with a vocal minority 
(as there often is in controversial issues), but against the 
unanimous opinion of scholarship since in this case there is not 
even a scholarly minority on the issue. Only popular and populistic
Islamic writers hold this opinion. If you disagree, then please 
give me some references to show otherwise. I don't pretend I have 
heard of all or read everything on the topic, but I have never 
heard of any scholar (i.e. with academic credentials) who has 
defended the authenticity of this book and done so in an academic
setting. But I am most willing to be informed otherwise.

Overview on the "Gospel of Barnabas"
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