According to tradition, the young prince Shakyamuni slipped away from his sheltered life in the palace and beheld, one after another, a sick person, an old person, a dead person, and a monk.
Each of these encounters was a profound shock. The first three "signs" brought Shakyamuni face-to-face with suffering. In the demeanor of the monk, Shakyamuni recognized the possibility of transcending suffering.
Ordinarily, to take the first steps on a spiritual path is to leave the world in some way. That is the point of monasticism, which provides institutional support for withdrawal. For laypeople as well, the early phases of a spiritual quest are typically directed inward. Yet all religions also offer teachings and practices that lead to a reintegration of spiritual and worldly life. One valid pattern is to find a path back into the world at a later, more mature stage of spiritual development.