Brida is the latest book by Paulo Coelho. It's about soul mates and such and gives an interesting perspective about love and success. Following is a quote from the book. Although I don't agree much about the "appointed path", I think its a good quote overall.
Never stop having doubts. If you ever do, it will be because you've stopped moving forward. And at that point, god will step in and pull the rug out from under your feet, because that is his way of controlling his chosen ones, by making sure they always follow their appointed path till the end. If for any reason we stop, whether out of complacency, laziness or a mistaken belief that we know enough, he forces us on...Having the courage to take the steps we always wanted to take is the only way of showing that we trust in god.