Yesterday I went out on a 4 1/2 mile run after work to think on some ideas. I thought of a bunch of ideas; RPG on the story of Zacchaeus, puzzle for believers seeking the lost, and a match-3 game among others. However, the idea that seemed to stand above the others was to do a runner game. The obvious game would be to make a game where you play as Jesus or a believer and run after lost souls to catch. My twist is that you will play as the lost soul, running away from Jesus. As you run you'll accrue sin points.
When Jesus catches you, he will remove your sin points and match it with grace points. This brings in Romans 5:20-21 where it talks about how sin increased, grace increased. Then, you'll be able to use your grace points to unlock costumes, more characters to run with, and other things.