Four stages of enlightenment

The four stages of enlightenment in Theravada Buddhism are the four progressive stages culminating in full enlightenment as an Arahat.

These four stages are Sotapanna, Sakadagami, Anāgāmi, and Arahat. The Buddha referred to people who are at one of these four stages as noble people (ariya-puggala) and the community of such persons as the noble sangha (ariya-sangha).

The teaching of the four stages of enlightenment is a central element of the early Buddhist schools, including the Theravada school of Buddhism, which still survives.

In the Sutta Pitaka several types of Buddhist practitioners are described, according to their level of attainment. The standard is four, but there are also longer descriptions with more types. The four are the Stream-enterer, Once-returner, Non-returner and the Arahat.

In the Visuddhimagga the four stages are the culmination of the seven purifications. The descriptions are elaborated and harmonized, giving the same sequence of purifications before attaining each of the four paths and fruits.

The Visuddhimagga stresses the importance of prajna, insight into anatta and the Buddhist teachings, as the main means to liberation. Vipassana has a central role in this. Insight is emphasized by the contemporary Vipassana movement.

A Stream-enterer (Sotapanna) is free from:

A Once-returner (Sakadagami) has greatly attenuated:

A Non-returner (Anāgāmi) is free from:

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Wikipedia