Think about the story of the fiery serpents. Talk about having to act on faith. That is, just by looking at the serpents, the Israelites were promised to be spared what would otherwise have been a certain death. There was no natural explanation; their life depended upon a supernatural act on their behalf. How does that reflect the plan of salvation, as well? What should this tell us about just how helpless we are on our own, apart from God, for eternal life? How should this reality keep us humble?
In what ways might we, either as individuals or as a church, be making some of the same mistakes as the children of Israel made? Why is it always so hard to see our own spiritual weak points?