Castiel tilted his head and took a step closer to the man. He moved slowly, and deliberately, but was unafraid of the mortal as he reached out to take James' chin in hand, moving his face down slightly so he could take a true look into the others' soul.
He read the other for a moment, then released his chin and shook his head.
"You are not soulless. And you are not evil," he said, voice low but firm. He thought for a moment, then lifted one hand slightly, though nothing out of the ordinary seemed to happen from it. "I may be able to help the scars heal. To help you control yourself. But a mind is a delicate thing, and this is not my specialty."
He wouldn't pretend like he was half the healer that he was the soldier. His experience was primarily the physical wounds gained during combat, or fighting the grip of black magic. But perhaps he could ease the pain that prevented James from being able to control himself.