The king and the party are mad and actually fucking stupid. They fear someone who can 'resurrect' people and would be the greatest asset in war and against demons. Probably the only person who could bring hope to the people, knowing that even when there is death, the adventurers can still be resurrected and win in the end just because they think there is a possibility of him 'resurrecting demons.'
Who the fuck cares if you're strong enough to fight any dungeon you go through? You aren't overpowered enough to beat every fucking monster that comes your way. Good luck fighting the demons, absolute bunch of idiots. Hope one of them dies in a really stupid way and regrets it when they aren't being brought to life.