John 18:14 Now it was Caiaphas who advised the Jews that it was expedient that one man should die for the people.
Caiaphas' was giving good advice but I dont believe he really understood what he just said. It was extremely important that One Man, Jesus, die for the people. God spoke through a donkey, He can speak through a misguided high priest. He thought the romans would bring down wrath upon the Jewish people due to this Jesus. They were justifying killing Jesus. Reality, if Jesus didnt die, we all would be stuck in our condemned state.