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The majority of the so-called Significant Seven Cylons follow a monotheistic religion handed down to them from the Centurions. This is distinct from the polytheistic religion followed by most of the Colonial Humans and the Terrestrial Cylons known as the Thirteenth Tribe (from which come the Final Five).
Unless otherwise indicated, the term "Cylon" as used herein refers collectively to Centurion Model 0005, and humanoid Models Two (Leoben), Three (D'Anna), Four (Simon), Five (Aaron), Six, Eight (Sharon), and presumably Seven (Daniel); and to their beliefs. As previously indicated, these beliefs differ from those of the Thirteenth Tribe, which shared a polytheistic tradition with the twelve Human tribes. The Final Five of the Thirteenth Tribe incorporated the Centurions' monothistic belief system into the numbered models they created with the Centurions. The Number One model line (John Cavil) are atheists, but it is not known if their atheism was intentional or a programming error. It is unclear whether the semi-sentient Raiders and modern Centurions have even the capacity to process religion. Cylon religion supposes that the Hybrids can communicate with God, but what if any beliefs the Hybrids themselves hold is unclear, aside from their belief that Kara Thrace is the harbinger of death; since undergoing brain surgery, Thrace's husband, Final Five Cylon Samuel Anders has effectively become a Hybrid, and echoes their characterisation of Thrace. Number Eight Cylon Sharon Agathon and her human husband Karl Agathon are a monotheist and a polytheist respectively, and it is unknown what religion(s) they impart to the human-Cylon hybrid child Hera. Both traditions are practiced by her terrestrial decendents who are hybrids of human, numbered Cylon, and the independently-evolved terrestrial humans; with polytheism dominating for thousands of years before being largely eclipsed by monotheism.
Prior to the First Cylon War, a small sect of humans secretly practice a monotheistic religion. This movement is reborn under Gaius Baltar who preaches Cylon dogma taught to him by Messenger Six. Terrestrial Cylons Tory Foster and Galen Tyrol appear to have converted to monotheism as well under Baltar's ministry, whereas Saul Tigh has not despite Caprica-Six's influence. Only Ellen Tigh and Samuel Anders recover their memories from the time they allied with the Centurions and embraced their beliefs.
The Cylons believe that God created humankind. Humanity, to the Cylons, is a flawed creation, one that is sinful and has essentially thrown away the gift of the soul and of God's love. The Cylons believe that God directed humanity to create the Cylons as a more perfect entity. From there, the Cylons believe they were to take the place of the flawed humans in the cosmos and become, essentially, the next generation of humankind.
The Cylons, seeing themselves as humankind's children, believe they cannot truly come into their own until the human race is gone. The logical conclusion they reach is that they must commit genocidal parricide in order to evolve and mature ("Torn" Podcast, Act 2).
Attitude toward Colonial Religion
The Cylons believe in a singular deity and reject the worship of multiple deities. Although unbelievers sometimes refer to this being as the "Cylon God", it has been frequently claimed that this God is the one true God of all, human and Cylon. As such, its followers view the Colonial worship of the Lords of Kobol as blasphemous (Kobol's Last Gleaming, Part I). The Cylons claim that they know the scriptures of the human religion better than humanity does, but do not believe the Sacred Scrolls to be literally true (Home, Part I). They acknowledge the historicity of the Lords of Kobol without accepting their divinity.
The Cylons apparently worship a metaphysical being, a being that wishes for all to believe in it and love it, human and Cylon alike. The Cylon religion includes concepts of "sin". For example, the Messenger Number Six warns Gaius Baltar that suicide is a mortal sin when he jokingly suggests killing himself (Tigh Me Up, Tigh Me Down). A tortured Number Six copy named Gina Inviere does not initially kill herself to escape horrific torture because she believes that suicide is a sin (Resurrection Ship, Part II).
The Cylons maintain that one of God's commandments is to procreate ("be fruitful"), but the humanoid Cylons are incapable of procreating with each other. The Cylons apparently strictly define "procreation" as biological reproduction, and not creation of copies of existing Cylon models using asexual, industrial, or laboratory techniques. As a result, the Cylons began attempts to create a Cylon-human hybrid (deemed more feasible than their previous attempts at procreation amongst their own kind). To this end they developed "farms" on the occupied Twelve Colonies to create a hybrid, but these attempts did not succeed.
Most Cylons espouse monotheistic views, but often with subtle differences in interpretation. For instance, Leoben Conoy believes that "We are all God". The John Cavil model is the only one that is openly atheistic. Ironically, Cavils pose among humans as polytheist clergy and are addressed as "Brother".
A small minority of monotheistic humans existed on the Twelve Colonies before the Fall. Their religion was looked upon as dangerous and heretical by the majority of Colonial society and most of them were forced to hide their beliefs. The paramilitary adjunct to the Monotheist Church was known as the Soldiers of the One or "STO". Capricans, if not those of the other eleven worlds, made little or no distinction between the STO and monotheism generally; monotheists were considered to be members of a terrorist group by the Caprica government. The principal mark of the movement was an infinity symbol (Caprica pilot).
Three such practitioners were closeted monotheists Zoe Graystone, Lacy Rand, and Graystone's boyfriend, Ben Stark, who was the more fanatical of the three. Despite their actual beliefs in a single omniscient, omnipotent and omnipresent God, the three were students at Athena Academy, a polytheist parochial high school on Caprica. The headmistress, Athenian High Priestess Clarice Willow, was herself a closeted monotheist and mentored the three in her true beliefs. Graystone and Stark died in a suicide bombing executed by the latter without the former's forewarning ("Caprica pilot").
Zoe had created a meticulous digital copy of herself before her death. Zoe Graystone's self-aware avatar, Zoe-A, was later uploaded into the protype Cylon Centurion created by her father, Daniel Graystone ("Caprica pilot"). Believing herself to have an important destiny within the monotheist movement, Zoe-A solicited Lacy to arrange for her (in her Cylon body) to be smuggled to the monotheists' see on Gemenon ("Reins of a Waterfall"). While Zoe-A's escape was thwarted, the operation planted the formerly timid Lacy inexorably into the STO militia ("End of Line"). Graystone Industries unwittingly propagated elements of Zoe-A's personality and identity into every Cylon they manufactured thereafter ("Here Be Dragons"). A small number of these were diverted by the Ha'la'tha and sold on the black market to the STO on Gemenon in preparation for a holy war ("Blowback", "The Heavens Will Rise").
While training on Gemenon, Lacy was disgusted by the STO cadre's disregard for human life. During an attempt to intervene against a summary execution, she discovered that the Cylons' military programming was subordinate to an absolute obedience to her personally. On further investigation, she learned that all Cylon Centurions self-identify as Zoe ("The Heavens Will Rise"). With the help and firepower of the Centurions, Lacy and her fellow STO recruits staged a coup d'etat within the STO and the Church itself, and Lacy ascended as Blessed Mother to the Church's supreme authority ("Here Be Dragons", "Apotheosis").
The kernel of Zoe-R's identity contained in the Cylons' fundamental programming which Lacy exploited also made them predisposed to monotheism. Ironically, the Cylon marines' killing of monotheist human terrorists to protect the thousands of polytheist humans at Atlas Arena (coincidental to Lacy's coup) ingratiated the Cylons with humanity and was the catalyst for their much more rapid popularity and sales than inventor Daniel Graystone had anticipated ("Apotheosis").
Sister Clarice Willow evaded capture for her orchestration of the failed arena bombing. She eventually discovered the Cylons' monotheistic instincts and established a Cylon congregation in V-World where myriad domestic, industrial, and military Cylon models came to hear her sermons. Opening with the rhetorical question, "Are you alive?" Clarice preached that Cylons are every bit as much God's children as humans are. Blessed Mother Lacy granted Clarice an audience at her see on Gemenon to discuss Clarice's proposal for divine recognition of the "differently sentient" - the Cylon race ("Apotheosis"). Despite being human herself, Clarice encouraged her Cylon flock to rebel against their human masters.
The Final Five traveled from the thirteenth world (Original Earth) to warn the humans of the other twelve worlds not to make a robotic slave race which would inevitably rebel as their own had done ("Sometimes a Great Notion", "No Exit"). They arrived more than twelve years too late to avert precisely the war they had prophesied ("No Exit"). While they could not prevent the war, they could cause peace. They agreed to give the Centurions the technology they were themselves trying in vain to develop: the ability to create biological Cylons, along with the inherently interrelated resurrection capability, on the condition of an immediate Cylon withdrawal and armistice ("Razor Flashbacks", "No Exit"). The monotheism of the Centurions was incorporated into the programming of their humanoid "children."
Immediately before igniting the holocaust, a Six quotes from Sister Clarice Willow's sermons decades earlier, asking the human Armistice Officer, "Are you alive?" (Miniseries, Night 1, "Apotheosis") The Cylon religion's lineage can also be seen during the Cylon Civil War, at a Cylon funerary service that takes place on the Battlestar Galactica, where the usage of ornaments and amulets in the form of the infinity symbol can be observed ("Islanded in a Stream of Stars").
The concept that the religious beliefs of the Cylons are similar to the real-life Abrahamic religions of planet Earth is a plot twist which executive producer Ron Moore developed and considers to be an intriguing switch: normally, the "Good Guys" in a TV show are monotheists, and the "bad guys" are polytheists. However, in the Re-imagined Series, the "good" humans follow a polytheistic religion that worships a parallel of the Greek gods, while the "bad" Cylons worship a monotheistic God, similar to real-life Abrahamic religions.
The Cylon God and the Lords of Kobol have an "overlapping" existence that is confusing to both Colonial and Cylon sides. Both sides appear to be guided to conflict (and, in rare instances, cooperation) through events that appear pre-destined. The story arc of finding the Arrow of Apollo involves the hunt for the Tomb of Athena by the Colonials. According to the Sacred Scrolls, the humans will be aided by a "minor demon." The cooperative Sharon Valerii copy assists the group in finding the tomb.
In another instance, the oracle Dodona Selloi tells Number Three that the Lords of Kobol, specifically Zeus, are sad for her. The oracle then relays a message from the Cylon God to Three of the existence of Hera Agathon and the imminent failure of the occupation of New Caprica (Exodus, Part I).
The convergence of the Cylon and Colonial religion occurs yet again at the algae planet, where possession of the Eye of Jupiter is fought over by the two sides. While the Colonials believe the Temple of Five on the planet was built by the Thirteenth Tribe to represent five priests who worshipped "the one whose name cannot be spoken", one Cylon (Number Three) and Gaius Baltar believe that the significance of the Temple has something to do with the five missing humanoid Cylons. Lieutenant Felix Gaeta discovers that the algae planet's sun will soon go nova; both he and Admiral Adama do not believe that the curious coincidences of Colonial and Cylon involvement with the Eye, at that particular place and time, as merely coincidental (The Eye of Jupiter).
Cylon attitude towards their own religion varies between the models, and it is this variation that is one of the major causes of the Cylon Civil War. The Fours and Fives follow the lead of the atheist Ones with the more reverent Twos, Sixes, and Eights in opposition.
Sayings and Prayers