Idealism (christian eschatology) is a type of belief that Christians have about what will happen at the end of the world. It means that the world will eventually become perfect. God will make sure that everything bad and wrong will be gone, and only goodness and love will remain. Jesus will return to the earth and the good people will be taken up to Heaven and live with God forever. The bad people who don't believe in Jesus will go to Hell and be punished for their wrong deeds. This is called the "Last Judgment".