I did housekeeping for a conservative Jewish family while I was in seminary. They kept kosher and were shomer shabbos. I was expected to, to the best of my ability, keep Torah in their home as well. I began to realize that this was not a burden, and that it did in fact lead to something close to mindfulness. Every moment of their day, every decision however basic, was a religious act. What they wore, what they ate, how they ate it, all were expressions of their faith. Unlike a good many Christians, they didn't and couldn't take their faith out and wear it one day a week. It was the essence of their life. On my first day of work, the woman I worked for went through the basics of kashruth, much of which I knew from my study of scripture. She showed me the things I needed to know--which were meat dishes, which for milk, etc. I was carefullly taking all of this in, worrying that I might make a mistake, when she said something of extreme importance: "But if you make a mistake, don't let it bother you. We do these things because we love God, not because we're afraid of going to hell. In fact, we don't believe in hell."
While in college, I interacted with many Christians for whom hell was a primary motivator, particularly when sharing their faith with others. If 'God loves you' wasn't enough to reel someone in to Christianity, perhaps fear of hell might.
The notion that one helps the poor, goes to church, practices the various spiritual disciplines, prays, or participates in any other aspect of Christian life because one loves God and wishes to follow Jesus to the best of one's ability is the true heart of discipleship. Fear of punishment, while in some cases effective, is not what Jesus was about. It's about who we are called to be rather than who we're not called to be.