Good words from Scot McKnight:
If you are a Christian, and by that I mean if you "believe" in King Jesus and you follow him, apologetics will be unavoidable at two levels. The first level is in your own head as you seek to make sense of your Christian faith, and this “in your head” level of apologetics is a life-long process.
The second level is "in the cafe" where someone asks you about what you believe and you realize you are being asked in the ordinary plane of life why you believe what you believe. This is your public confession, and when I say there is often conflict between the "in your head" and "in the cafe" levels I mean many are not willing to trot out the doubts in their head when they are "in the cafe." One could say "in the head" apologetics is less confident than "in the cafe" apologetics.
So most folks seek what might be called "cushions of confidence," places in their faith where they find soft, comfortable places and where they can feel confident about their faith. Some folks seem to be totally confident about everything in the faith and I don’t think it would be anything but truthful to say this about someone like Norm Geisler. But for many there are places in the faith where they are not so confident — say atonement theories, views of Scripture that conflict with their instincts when they read the Bible, apocalyptic worldviews, homosexuality — and others (cushions of confidence) where they are confident — Jesus himself, his kingdom vision, loving God and others, redemption in Christ, the afterlife.
You can read the entire post, "Apologetics Is Unavoidable," here.