One would think that Moshe Rabbeinu, who is presently interceding on behalf of Bnei Yisrael, would attempt to decrease the seriousness of their sin, not magnify it. Horav Yechezkel, zl, m’Kuzmir (Maamer Yechezkel) explains that the first step on the road to teshuvah, repentance, is hakoras ha’chet, recognizing and acknowledging that one has sinned. One who puts his head in the ground in an attempt to ignore his misdeed, or rationalizes his actions with a list of excuses to absolve – and even justify – his wrongdoing, will not repent. Even if he makes a feeble attempt at teshuvah, it will have little to no effect, since he has not acknowledged his sin.
Adam HaRishon sinned, and his teshuvah was considered deficient. The Rebbe explains that Adam did not view his actions as being particularly sinful. Chavah not only had initiated it, but, as Chazal (Bereishis Rabbah 19:5) teach, she wailed until he ate. This is sufficient rationalization to diminish the severity of the sin. When the sin is not clearly defined, the repentance either does not follow or, at best, is flawed. This is why Moshe magnified the people’s transgression concerning the Golden Calf. Once the sin had been clearly delineated and the spiritual stain outlined in all its gory detail, the people understood the need for repentance. Thus, what would appear to be Moshe’s condemnation was actually his manner of encouraging and facilitating their teshuvah.
