A client with an accomplished and varied background came to me with this specific question in mind as she approached her 60th birthday. She went to a short and simple lifetime in pre-Roman Israel where, as a builder, her prior personality (a young man) traveled the countryside, working on houses and buildings for other people, and sent money back to his mother and sister. Sadly, he died quite young in a building accident on a large project, one that was beyond his usual scope.
How did this relate to my client's current mission or purpose? A key theme was helping others, not putting ambition (that larger project) ahead of more humble but valuable work. But most importantly, the client's spiritual guidance came through to let her know "you are enough; you don't have to be anybody or anything else, justify yourself or make up for anything... it's not about what you DO it's about being open, accepting, living with integrity."
A few months after the session, the client reported that she felt a noticable decrease in her level of anxiety surrounding the whole "what to do with my life" issue. "Just by 'being me' I seem to have more of an impact on the lives of others than if I was engaged in some 'important' work." She concluded that the regession "was one of the most intense hours of my life, and I am so thankful I got the chance to meet such a thoughtful and giving young man - and to know that he was me!"