Locked away? What was he talking about? There was a way that he could get his John back?

"He won't be the same, he won't look the same or act the same, he won't be the same John, even if he does get the memories back." Sherlock argued.

"Why would I have to relocate out of Hell to make John remember again?" It made no sense. He had no want to go back to the Overworld. "Besides, I can only go back and forth from Hell once a year. It wouldn't be very .. convenient to ferry souls."