He hates evil, because it causes pain and suffering to the people he loves. So in Jesus, God accepted the suffering of sin himself, showing that he has the right to forgive our sins. The barrier between us and God is removed. We can return, if we want to. In a way, all humanity has a mistaken identity.
People think they can be self-sufficient and make their own way in the world.
But an identity without God is a mistaken identity. Many are sadly misinformed about what God is like. They've heard that he is mad at the world, ready to incinerate it. This is also a case of mistaken identity. What God is like is perfectly revealed in Jesus Christ.