The Cleric was an alien who was part of an intergalactic missionary group known as the Holy Commune who journeyed from world to world to preserve their culture by use of several technological artifacts known as The All. These devices imprinted the beliefs of the religion and linked the many followers together. At some point in the distant past, he arrived on the planet Krypton during its Fifth Age where he sought converts to his beliefs. He eventually found many Kryptonians that accepted his peaceful teachings and flocked to his banner.
In time, the Cleric would denounce the Kryptonian practice of making clones for use as spare parts. His arguments since cloning did not replicate the soul and, furthermore, the clones had a right to life as living beings. Amongst those that became disciples of the Cleric was Tyr-N, Syra and Sen-M; the latter of whom helped create the Clone Rights Movement as well as the "League of Life".
The Cleric's word eventually forced the Kryptonian ruling elite to create a weapon developed by Kem-L for use against the alien which became known as the Eradicator. Syra later informed the Cleric and urged to make a pre-emptive strike, while the Cleric spoke words of pacifism, his followers decided to act on their own. He later attempted to dissuade the situation before it erupted into violence by offering to take himself as well as his followers into space but was answered by an energy blast from the Eradicator that had been activated. Despite being created to kill him, the weapon simply caused pain and rendered him unconscious. This sparked a fight between the followers of the Cleric and the Kryptonian elite where one soldier caused an explosion when they incorrectly operated the Eradicator controls. This event would be referred to in the annals of Kryptonian history as the Day Of Intolerance.
This forced the Cleric to take control of the device, and he decided to leave Krypton with his faithful followers onboard a space ark, though he left a small number of this commune behind whom were led by Sen-M. However, tragedy struck when the Kryptonian pilgrims began dying one by one whereupon the Cleric came to the realization that a genetic link to their homeworld kept the inhabitants of Krypton bound to it. Feeling responsible for their deaths, the Cleric went into a self-imposed exile as he believed himself responsible for their deaths. Furthermore, he kept the Eradicator, though unknown to him, the device became bound to him and preserved his life by enhancing his life span over the years allowing him to continue with his existence for over two hundred thousand years.
His existence remained isolated and empty until a chance meeting with the last survivor of the planet Krypton which had long ago been destroyed in a violent cataclysm. This Kryptonian, known as Kal-El, had been taken from his adoptive world of Earth and forced to fight in the gladiatorial arenas of Warworld by Mongul. During that time, the Cleric formed a strange mental connection with him where they exchanged memories.
It was during that time that the Eradicator informed the Cleric of Mongul's intention to kill Kal-El to which the alien missionary sought to preserve his life. Teleporting him away to an asteroid, he urged Kal-El to allow the Eradicator to heal him and the two linked mentally where they relieved their darker memories. The Cleric relived the moment of the death of his followers while Kal-El relived his killing of the criminals from the Phantom Zone. The act healed both men and the Cleric decided to pass on the Eradicator to the last survivor of Krypton.
After giving Kal-El the Eradicator, the devices influence on the Cleric's body faded and the alien rapidly aged to the point that his life could no longer be preserved. His last words to the Kryptonian was to see his face without a beard to which Superman complied by using his heat vision to shave off his beard after which the Cleric died. Kal-El later made a grave for him on the asteroid and left the "S" symbol on it to mark the resting place of the Cleric.
Despite his death, the memory of the Cleric remained within the Kryptonian artifact known as the Eradicator. When the device began causing a string of incidents around the planet Earth, Superman journeyed into its memory where he met a representation of the Cleric within it who explained the purpose of the machine; to eradicate all life except for Kryptonian life on a planet as part of its directive.
The memory of the Cleric remained within the Eradicator and it was revealed that it contained the virtual personalities of past users. When Dr. David Conner of S.T.A.R. Labs bonded with the device, he faced a moment where he was overwhelmed by the machines programming. However, the Cleric praised the Eradicator for fighting its original programming and stated that it was responsible for not originally destroying the alien missionary thus allowing him to preach his peaceful message to Krypton. 
- 11 Appearances of Cleric (New Earth)
- 3 Images featuring Cleric (New Earth)
- Quotations by or about Cleric (New Earth)
- Character Gallery: Cleric (New Earth)