Hi,
First I would start with 3 questions
What EXACTLY do you believe?
Why do you believe it?
Where did you get your info.?
Most people when asked those questions dont really know the answers. Get this person to p(name removed by moderator)oint their objections so you can then p(name removed by moderator)oint your answers.
Like others have said here–pray—tell them what you believe and why.
A good book to get is The New Evidence that demands a Verdict by Josh McDowell
He gives info. on why the bible is reliable to believe.
But in the end–keep in mind(so you dont get frustrated)that to nonbelievers the bible is foolishness.
Another thing I have pointed out to people is—what human in their right mind would write some of the stuff in the bible that we are to follow and then DIE for what is written in there!!
Think about some of the principles we are suppose to follow–what human really wants to follow some of those-- and as you see we dont but we try hard and why is that? It could only have come from God.
These are just very few suggestions–hope it helps