The Shrive (German edition: Symbol der Reue, that is "symbol of regret/remorse") is the key to the Soulstone and the device that can lock up the evils of the world into a lesser form for another thousand years. It is connected to the sword Eternity which was taken from the Soulstone by Claude Florentine.
The Shrive can only be held by someone who has received the marks, by sitting on the gloomy, viridescent bone throne (which bears the Shrive symbol on top). Belial has procured a set of gloves, apparently made from the skin of somebody branded with these marks:
Adam explains that "the artefact is communicating with me - with the brands. Something's passing between them, and I'm right in the middle of it. It's as if there's something else, some power, manipulating and pushing me first this way, then the other. And it's powerful... like nothing I've ever felt before."
The design of the Shrive, specifically the ornament in the center of the artifact, is reminiscent of the globus cruciger, a symbol of authority extensively used throughout the Middle Ages which symbolises Christ's (the cross) dominion over the world (the orb), literally held in the dominion of an earthly ruler (or sometimes celestial being such as an angel). Apart from that, the "cross" could also stand four the sword Eternity stuck in the "orb" which is the Soulstone.