We are studying Bible with a Muslim friend who is asking us a lot of questions. For him it seems like the Bible is self-contradictory. For example, he finds contradictions in the books of Samuel, Kings, and Chronicles. And Matthew doubles the number of demoniacs healed. What should we say? -- G.B. 
Answers to most of these questions are at the website. Just search. Fortunately, the message of scripture doesn't depend on error-free manuscripts. Even if we find actual mistakes, the message is the same. Those who link their faith in scripture or God with inerrancy -- the notion that God would have protected scripture from having an errors -- are forced into an unnecessarily defensive mode. If a scribe left out a word, they need an explanation. If a number was incorrectly copied in 1-2 Kings (a common occurrence), then they feel uneasy, and have to make all sorts of assumptions to rescue their theology. If Matthew doubles the number of demoniacs, they either have a meltdown or have to assume that the other writers deliberately ignored one of the demoniacs.
(Actually, Matthew doubles the number of servant girls who accuse Peter -- I comment on this in a recent podcast -- the number of lepers, the number of demoniacs, and the number of blind men Jesus healed [twice!]. We may not feel comfortable with what Matthew did, but he had good reasons to do so and people of his time would have appreciated his intention. For more on that, please see my N.T. chapter notes.)
It's important that we appreciate the human dimension of scripture. Just as in the incarnation, God uses a limited and lower vehicle to reveal his will to man -- our language. Books and stories have limitations, as does copying, cultural expectations, literary conventions, etc. But it is in just such an earthy and natural mode that the Almighty God comes down to our level.
Someone can use the surface contradictions or minor errors to write off God and the Bible -- he has allowed that to be an option. I am not referring in insoluble and significant contradictions -- e.g. if the Bible taught that Jesus was a man who lived in the 1st century and it also taught that he came to earth, lived and died as an Egyptian Pharaoh 2000 years earlier! Yet for those with good hearts, the message, unaffected by such minor things as are bothering your Muslim friend, comes through loud an clear.