The first role in life is that of a student. If a person were to observe this strictly, they would spend a few years of their youth studying and memorizing Hindu scripture. They would work with a teacher who would direct their spiritual growth.
After that, the person becomes a householder. In this stage, the person is a responsible member of society who is making a living and raising a family. The man is expected to ensure that the proper methods of worship are observed in his home.
The third chronological age is that of retirement. A retired man has fewer duties either in terms of society or religious ritual. He is free to become more contemplative and spiritual.
At any point in one's life, one may become an ascetic, which can be seen as a fourth stage of life. A person who chooses this rejects all the duties of normal life. He becomes an ascetic who lives only to try to attain enlightenment and wisdom.