Ceris was a member of a Triannon religious faction that believed the "Chosen Realm" was created by the "Makers" in ten days. His faction waged war with D'Jamat's faction, which believed it took only nine days.
After D'Jamat's forces commandeered Enterprise NX-01 in November of 2153, he engaged Ceris' ships. Ceris refused to surrender as D'Jamat demanded, even though D'Jamat offered to cause no harm to Ceris and his crew. Ceris said that he knew that D'Jamat considered him and his people heretics, and that he knew that they would be killed. The fighting ceased when the Earth Starfleet crew retook the ship and Captain Jonathan Archer informed Ceris about this. (ENT: "Chosen Realm")