Parashat Shelach Lecha is focused around the story of the spies, the meraglim, which is one of the defining moments in Jewish history. The sin of the spies is not only a key historical event that influenced the fate of the generation that left Egypt. It's greater impact is determining the day of national mourning for generations to come - Tisha B'Av.
Why did Moshe Rabeinu have to send spies in the first place if God commanded Israel to conquer the land of Canaan?
What is the sin that provoked such a strong consequence from God?
Rav Kilstein explores the deeper meaning of the spies through the commentaries of Rav Tzadok HaKohen on the Torah Portion of Shelach Lecha.