I work with an agnostic. I've shared my faith with her in a very nonconfrontational way for two years now. She's very quick to shoosh me, so I witness more in the gift of mercy and hospitality and less in prophet! Do you have a recommendation for a book that I could give her? She loves history and has a very inquisitive mind. She asks me questions quite often about the Christian "religion." She always has an audio book going in her car and at her desk, so audio would be ideal.
Have you seen Tim Keller's The Reason for God? I would recommend taking a good look at it. Keller is very reasonable, and I think he keeps readers from becoming defensive. Many unbelievers have listened to him speak in his church in NYC, and have read his books.