Back on Daribo, there were many religions, but those that went to Casti (the planet the Castithans eventually settled) were followers of Rayetso. The dictates of Sherivano had been handed down from generation to generation, and when worshippers of Rayetso went to Casti, they took those scrolls with them. With the coming cataclysm, there was a schism on Casti. Many believers felt Casti could not be abandoned, and it was they who retained the scrolls. Datak's father must have been a deeply religious man.