On the 8th day of the inauguration of the Mishkan, Yom Shemini L’Miluim, Aaron and the Bnei Yisroel brought special Korbonos. Although Aaron brought an Egel for a Korban Chatos, the Bnei Yisroel brought an Egel for a Korban Olah. Why would the Torah differentiate between the Korban of Aaron and the Bnei Yisroel, if both of them were involved in the Chet HaEgel?
Kli Yakar explains, that there was a fundamental difference between the sin of Aaron and the sin of the Bnei Yisroel. Aaron’s sin was only “BiMaaseh” – with his actions and not with his Machshava – thoughts. He did not intend to worship the Egel, just to create it, in order to buy time until Moshe would come. Since he only sinned with his actions, he brings his Egel for a Chatos, which atones for sins done through one’s action.
However, Klal Yisroel sinned also with their thoughts. They DID intend to worship the Egel. They therefore had to bring the Egel as a Korban Olah , which atones for sins that involve Hirhur – prohibited thoughts.
