The Prophet of Conviction was a representative of the Covenant High Council who was sent to Kholo in 2539 to oversee it's destruction.
Stationed aboard a ship in the Fleet of Righteous Vigilance, Conviction personally ordered it's Shipmaster to burn a Covenant religious symbol on the surface of the planet as a symbol of the Covenant's triumph. Following this, with the ship becoming the Prophet's permanant home and mobile command post, the fleet carrying out Conviction's bidding throughout the rest of the war.
During the Great Schism, as the Shipmaster received the first news of the ascension of the Brutes and the slaughter of the Elite councilors from the Fleet's Admiral, he rushed to the Prophets personal quarters. Conviction was ready, having been told that his race's deception has been exposed. The Prophet attempted to kill the Shipmaster with his Plasma Pistol, but he failed and ended up subdued. The Elites dragged him before the crew in a public execution, after showing them the images of the Brute's treachery. Upon seeing the Prophet awaken and terrified of being surroundered by angry Elites, the Shipmaster crushed his neck, thus killing the Prophet of Conviction.