SimchaMinute by Rabbi Avigdor Miller
This is a world of tests. We are tested in This World by false things, by illusions. We will not merit to see the full truth in This World, only in the World to Come. Thus, there has to be another world.
That is where Hitler is right now, being punished with an awesomely fierce punishment. The righteous are witnessing it in the World to Come. That’s part of their reward, seeing the righteousness of Hashem’s Wisdom. As they are in the Next World, they are not being tested any more and they are allowed to see the truth. — Ohr Avigdor Shaar Bechinah