From Halopedia, the Halo wiki
Cleansing Truth, alternatively known as Cleansing Faith, was a Covenant frigate in the post-Human-Covenant War era, under the command of the Servants of Abiding Truth. Galur was the shipmaster or the ship. Cleansing Truth was about to become a vessel for the Abiding Truth for their eventual regrouping and attack against the Arbiter after their defeat at Vadam, until its destruction at the hands of the Arbiter's Swordsman.
List of appearances