There is no easy answer to this question because it depends on the person and the situation.  No single answer works every time.  Therefore, you must first ask questions and discover what the person believes before you start defending the Bible.  Ask if the person is an atheist, a Muslim, a skeptic, or an agnostic.  Ask if he believes in evolution, aliens, or nothing.  Ask if the person believes in God.  If so, which kind?  Does he believe that God is in us all, or that God is part of the universe, or if God is a personal being?  You have to ask questions before you begin teaching.  You must first find out what the person’s assumptions are and then tackle those assumptions.  You must prepare the ground before planting the seeds.  See if the person’s assumptions are logical or not.  See if they agree with the facts concerning history, the Bible, Christianity, or other topics.  Find out if the person is just being difficult or actually wants to talk.  All of these things are important and affect how the conversation will go.

Take an atheist, for example.  He won’t believe the Bible is the word of God because he doesn’t believe in God.  So, you first have to discuss the issue of God’s existence.  A Muslim, on the other hand, believes in a god but doesn’t believe the Bible because his religion tells him it has been corrupted. He will undoubtedly bring up alleged contradictions in the Bible in an attempt to discredit it.  A Hindu might not even know what the Bible really is.  A Buddhist really doesn’t believe in a God, so that is a hurdle you’d have to get over.  You must ask questions to find out about the person.  Here’s a brief outline of how to do this:

1. Ask about the person’s beliefs:  Does he believe in God or not?
   1. If the person does not believe in God, then you must discuss this before getting to the Bible.
   2. If the person believes in God, then…
2. Ask what religion the person is:  Buddhist, Hindu, Muslim, Mormon, etc.
3. Ask why the person does not believe the Bible is the word of God.
4. Ask “why” to the answer.  Sometimes it is good to repeat the answer in the form of a question.  For example:
   1. If the person says the Bible has contradictions, ask “Why do you believe the Bible has contradictions?” or “Do you have any examples of contradictions?”
      1. If the person gives you some, then examine the texts to see if it really is a contradiction.  If you don’t know the answer, say you don’t, do some research, and provide the answer later.
   2. If the person says he just doesn’t believe it is God’s word but doesn’t have any real reason, then ask “Why not?  Do you have any solid reasons for this?”
      1. Listen to the answer and ask more questions.  Learn more.
5. Examine the answers given to you to see if they are illogical, inaccurate, or emotional.
   1. Illogical:  Sometimes peoples’ criticism of the Bible is not rational.  For example, someone might say that the Bible can’t be God’s word because it is ancient.  But being ancient doesn’t mean it isn’t from God.
   2. Inaccurate:  Sometimes people have inaccurate information about the Bible.  For example, someone might say that it is nothing more than fictional stories, or that it has been changed so much it can’t be trusted.  But the truth is that it is not fiction and it has not been changed.
   3. Emotional:  Sometimes people just hate religion, God, or anything that imposes morals.  Other times people hate the idea that Jesus is God in flesh, or that He is the only way to salvation.  Emotions must not be brushed aside.  Listen to their responses and gently correct and point people to God.