Bajoran philosophy was filled with spiritual and religious overtones. Bajor was a world with a rich, full culture. Millennia ago, while Humanity was still learning to walk upright, the Bajoran people were thriving, while during the 16th century they were even building spaceships that could travel light years in a relatively short span of time. (TNG: "Ensign Ro"; DS9: "Explorers") Their philosophy was driving them to make these advanced strides in technology and culture. They believed in deities they called the Prophets. To those in Starfleet, the Prophets were non-corporeal aliens that had created the only stable wormhole known to exist. They did not perceive time linearly, as did corporeal beings. Tens of thousands of years ago they left pieces of themselves, known as orbs or the Tears of the Prophets, on Bajor for the inhabitants to find. (DS9: "Emissary", "Tears of the Prophets") These orbs offered visions to various Bajorans and resulted in their sacred writings and prophecies. There were different types of orbs, such as the Orb of Prophecy and Change and the Orb of Time. (DS9: "The Circle", "Trials and Tribble-ations", "Wrongs Darker Than Death or Night")
Then the Cardassians came, unleashing a sixty-year occupation that stripped the planet bare of its resources. Over the years, this gradually changed the Bajoran society, from being a relatively peaceful and prosperous people to being aggressive, destitute guerrillas. Before, they did bicker among themselves, but later, were united in an effort to rid their planet of the Cardassian force. The underlying core of their faith and philosophy remained the same and it was this that ultimately pulled them through this dark chapter of their history. When the Cardassians were finally gone, the bickering resumed.
As a result of the occupation, the Bajorans became very distrustful of outside cultures. They did, however, realize their vulnerable state and invited the Federation to establish a presence in their system to ward off any vulture species or the return of the Cardassians. (DS9: "Emissary") Some more conservative sects, such as that led by Vedek Winn in 2370 on the space station Deep Space 9, blatantly disregarded many scientific facts simply because they did not agree with the ideals of their faith. Other, somewhat more liberal sects, such as the one led by Vedek Bareil, were more open to the ideas of science and religion complementing one another. (DS9: "In the Hands of the Prophets")
The Bajoran deities did not end with the Prophets. The embodiment of all that was evil in their society was the aliens they called the Pah-wraiths, or in some instances, the Kosst Amojan. Captain Benjamin Sisko became the Emissary of the Prophets in 2370, while in 2375, Gul Dukat became the Emissary to the Pah-wraiths.
Overall, the core of the Bajoran religious system included an undying faith in the Prophets, and their plan for Bajor and all Bajorans. This, along with charity and humility, were the keys to enlightenment. (DS9: "Covenant")