Crypt of the Hushed Lamb. The Nephilym Chronicles, #7

The birds have stopped singing in Kerrvall. Amidst the black mud and relentless autumn rains of the Rhogrik lowlands, Sir Carthys leads a horse into a town with its tongue cut out. He is the King's Falcon, bound soul-to-soul with the angel Valiant, but the celestial bond is fraying. They seek the Codex of Aiden, a heretical relic lost to time. Instead, they find a populace silenced under the sign of the Hushed Lamb.
Joined by Loriene, a revived general of the fallen Order, Carthys must descend into the damp, rotting crypt where one of his "fallen" brothers endures an eternal, agonizing stasis. When the Advisor's trap is sprung, Carthys must choose: uphold the laws of the King's Order, or risk his and his angel's souls to pull a comrade back from the void.