Which of the two major sins that Bnei Yisrael committed in the desert seems worse- Cheit HaMeraglim, the sin of the spies, or Cheit HaEigel, the sin of the golden calf?
At first glance, it seems that Cheit HaEigel was worse. After all, it involved Bnei Yisrael worshipping an idol soon after Matan Torah, and causing Moshe to break the Luchot. On the other hand, the essence of Cheit HaMeraglim was just Bnei Yisrael believing the lies that were told to them by their respected leaders. This does not seem as bad as worshipping a golden calf.
However, the punishment given to Bnei Yisrael for Cheit HaMeraglim was much worse than the punishment given for Cheit HaEigel. After Cheit HaEigel, Moshe called out the thirteen Middot of Rachamim of Hashem (34:6), and then Bnei Yisrael were completely forgiven. Regarding Cheit HaMeraglim, though, Bnei Yisrael received a far more severe punishment. First, an entire generation of Bnei Yisrael was condemned to die in the desert, and only the new generation would inherit Eretz Yisrael. In addition, the Gemara (Ta’anit 29a) relates that since Bnei Yisrael cried that night for no reason, Hashem punished them by making that night “a cry for generations.” This later became known as Tish’ah BeAv, the day of the destruction of both the first and second Batei Mikdash. The Gemara concludes that had Moshe led Bnei Yisrael straight into Israel and built the Beit HaMikdash without sending a spy mission, the Beit HaMikdash would never have been destroyed. Clearly, the punishment for Cheit HaEigel was much more severe than the punishment for Cheit HaMeraglim.
Why did Bnei Yisrael deserve a harsher punishment for Cheit HaMeraglim if Cheit HaEigel was a much worse sin? The Kotzker Rebbe explains that when Bnei Yisrael saw Moshe break the Luchot after Cheit HaEigel, they lost hope. Their relationship with Hashem appeared broken beyond repair. Bnei Yisrael felt a sense of disparity, which is the key to Teshuvah. If somebody can truly feel hopeless and desperate, the rest of Teshuvah is easy to achieve. Since Bnei Yisrael did full Teshuvah, Moshe was able to beg for mercy from Hashem.
However, after Cheit HaMeraglim, Bnei Yisrael thought that they could easily do Teshuvah and everything would be forgiven. The expectation that Teshuvah is easy to perform is an indication of trouble. Rambam (Hilchot Teshuvah 4:1) explains that if someone sins with the intention that they will eventually do Teshuvah and be forgiven, Hashem will not accept that person’s Teshuvah. After Cheit HaMeraglim, Bnei Yisrael’s Teshuvah was insincere. Although they went through the steps of Teshuvah, they didn’t have the proper intention, and thus their Teshuvah was not accepted by Hashem. This is the reason for the much more severe punishment of Cheit HaMeraglim.
The Kotzker Rebbe’s answer to this question teaches us that Teshuvah requires a brutally honest self-assessment. We must not just go through the motions of Teshuvah mechanically. Rather, we should understand and verbalize where we went wrong, and then our heartfelt Teshuvah will hopefully be accepted.