Well, I'm sure you could understand wanting to share something you've learned before you die, then.

[He stopped again and turned to Sherlock slow enough that it was obvious he wasn't trying to attack the other, one of his books was back open and he was obviously trying to show him a passage. Someone seemed to forget they were being held at wandpoint.]

Look at this, I think this is the answer [He pointed to one of the passages, who even knows what he could be pointing to, Sherlock you need to look, could be important.]