I am a initiated Nichiren Buddhist and will be formally initiated in the theravada tradition early next month. The purpose of religion in general is whatever your beliefs are, are those that shape what you do and how you do in regards worship, giving offerings, prayer, and/or so forth. It's what you do.
The Saddharma Puṇḍarīka Sūtra says
"The Law of the Buddhas is constantly a single flavor. Practicing gradually stage by stage all beings can gain the fruits of the Way. Those who are steadfast and firm in wisdom, who fully comprehend the threefold world, and seek the supreme vehicle to achieve growth and maturity, who dwell in meditation, in the emptiness of all phenomena. Through various causes and conditions, various kinds of simile and parable,opens up and reveals The Buddha Way."
We have the eightfold paths-right action, speech, concentration, meditation, intention, livelihood, views, effort, and mindfulness.
The Buddha goes into extreme detail here: Eightfold
Accesstoinsight
The keys to right speech
"Monks, a statement endowed with five factors is well-spoken, not ill-spoken. It is blameless & unfaulted by knowledgeable people. Which five?
"It is spoken at the right time. It is spoken in truth. It is spoken affectionately. It is spoken beneficially. It is spoken with a mind of good-will." —
AN 5.198 This is a very small excerpt.
The Buddha has a high emphasis on meditation as the purpose of religion (living the eightfold). The core of it is the Noble Truths-or Principles of Life. We all are born, age, grow ill, and pass away. We do this until we gain true understanding of this cycle of rebirth through samsara. When we have full understanding, we are enlightened and we die.
The purpose of religion is to understand and to practice in understanding literally life and death.