Prophet of Objection
From Halopedia, the Halo wiki
The Prophet of Objection was present during the trial of Supreme Commander Thel 'Vadamee, who would later be made an Arbiter. A devout follower of the Covenant ideology, Objection was angered by what he saw as the Commander's failure in the destruction of Installation 04. He thus led the call against the Commander and when the High Prophet of Truth remarked to the Commander that his mistake not to safeguard the Halo was a colossal failure, the Prophet of Objection stood up and shook his fist, saying "Nay, it was heresy!"
Later, the High Prophet of Truth dismissed this remark, saying that though the Arbiter rightly bore the blame for the destruction of the Halo, the council was "overzealous" in branding him a heretic for this failure.
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