Writing songs out of my faith was a real natural progression. I grew up singing in my dad's choir and singing with my family. Christian music became the music that I identified myself with and was a way that I expressed my faith. Even at a public school I would take my Christian music in and play it for my friends.
Rich Mullins was the uneasy conscience of Christian music. He didn't live like a star. He'd taken a vow of poverty so that what he earned could be used to help others.
I feel that Christian music is a subculture directed towards the Christians. It's not really being exposed to non-Christians and it's not really created for non-Christians, so non-Christians almost never hear any of this music.
As far as spiritual influences in Christian music, I would say Crystal Lewis - a lot of her songs especially. The ministry she has through her songs has really hit me.
I listen to a lot of Christian music, and reading my Bible calms me down immensely.