Although Fornax was once a stronghold of the Adeptus Ministorum, the disastrous events in the Anargo sector during the Age of Apostasy changed Fornax for millennia to come. Parallel to the disappearance of the Anargan Theocracy, the number of faithful worshippers on Fornax shrank drastically in only a few decades. The old colony, which had once been almost monolithic in its devotion to the Adeptus Ministorum, now experienced a drastic religious polarization. On one side, the majority of people on Fornax lost faith in the teachings of the Cult Imperialis, and scattered. Atheism became increasingly frequent, as did adherence to unofficial religions and beliefs. On the other side, however, the minority of faithful worshippers belonging to the Cult Imperialis grew increasingly fanatical, disgusted by the secularism that swept over their world.

The growing number of mutant rebellions on Fornax and alien attacks elsewhere in the Anargo sector have led to the appearance of various militant cults, such as Redemptionists. These militant cults constantly strive to inspire faith in those they find lacking, either by persuasion or force, and conflicts between militant cultists and non-religious groups are growing increasingly frequent.

Although this religious polarization is a significant problem on Fornax, the old philosophies of Fornaci priests and prophets remain as the foundation of Fornaci culture. Central to the old beliefs and their derivative philosophies is the Fornaci concept of beauty as the highest power in the universe. In the Fornaci mindset, beauty, whether in physical or abstract form, is an end in itself, but also a source of power for humans, and a way to worship and empower the Emperor himself. Although the religious beliefs behind this philosophy have faded somewhat over the millennia, it remains an important part of Fornaci culture and the mindset of its people. The Fornaci concept of beauty is known locally as ‘the divine beauty’ and its main principles are famously described a common mantra;

"In beauty, purpose
For beauty, sacrifice
With beauty, victory”

- The clover of firmament