He's literally a polytheistic soldier that was on a mission to destroy the chosen people, realizes the errors of his ways because of him being on a great journey to get the index (Damascus moment) and then becomes devoted to ensuring that the great journey (firing the ring) is done by the reclaimers rather then the false prophets. He also rejects his old name with the -ee at the end and fully embraces the title of arbiter. Redeeming himself and the title.

He even tries to convert Tartarus.