He doesn't understand what a show of trust it is, no. He takes the gem in his hands, but upon being told what it is he's very careful with it, and he soon sees that its lustre is being eaten away by something. He looks from it to Emet-Selch, his expression tinged with worry.

"Hades... you cannot." So says the man who sacrificed himself once so that their world might go on... but it's different! He and Emet-Selch aren't the same. All Hythlodaeus had was his soul to give, but Emet-Selch is so talented, so... special.

"Pray do not put yourself in danger. Our world is gone, there is naught that can be done for it now."