Some Muslim argument for the authenticity of the "Gospel of Barnabas" included this remark:

 b.   '.... not only those very leaves which, fifteen years before. 
   I had taken out of the basket,  but also other parts of the Old 
   Testament, the Hew Testament complete, AND THE EPISTLE OF BARNABAS 
   and a part of the Shepard of Hermes.  It is now well known that 
   the manuscript which Tischendorf so emotionally leafed  through 
   that night, there and then transcribing the hitherto LOST 'EPISTLE 
   OF BARNABAS'  and 'Shepard of Hermes was what we know today as 
   the Codex Sinaiticus 
      (Jesus: The Evidence, 'Discovering the documents,' pp. 17/18).    

There seems to be some confusion between the Epistle of Barnabas and the Gospel of Barnabas. According to current historical research, there is no evidence that these two are even related.

The following are known:

1. Epistle of Barnabas, written between AD 70 and 135, and contains two parts: general advice on church affairs in the first part, and the second part answers the question on whether Christians need to observe Jewish food laws, etc. His answer was that these laws were symbolic in nature.

2. Journey of Barnabas, a 5th century work to supplement the account in Acts.

3. Gospel of Barnabas (I), rejected among a list of forgeries in the 6th century. Nothing else is known about this. Not known if it has anything in common with (4) below.

4. Gospel of Barnabas (II), Latin manuscript from Italy in the 16th century, translated into English by Lonsdale and Laura Rigg, published in 1907 by Clarendon Press, Oxford.

Documents (1) and (4) contradict especially in their views of circumcision and Jewish food laws. (1) takes the view that these are symbolic, while (4) are universal and all are obligated to observe. (1) emphasizes that we are to find our salvation in the cross of Jesus while (4) states that Jesus was not crucified.

The "Gospel of Barnabas"
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