The Gemara says that we gave half a Shekel to be Mechaper on the Egel
that was done at Chatzos, or six hours. If they would have done it
later it would have been worse? Had they done it in the morning one
Ma'a would suffice?
It is possible to answer that both would have been worse since it
would show Zerizus to an Aveira or planning of one. Having been by
Chatzos shows that it was one out of rashness aandd yet not through
Zerizus. This might be why we merited a Kappara in the first place.
More importantly though, the price is not important. No one went broke
over a half Shekel. The price, or weight, when it matches something
can come in place of it. This is what we find in Maseches Shabbos,
that if you find something whose weight matches that of an Even Tekuma
it can take it's place. Gematria too, works in a similar vein. Having
the same numerical value doesn't mean it is the same word. It means
that it can switch places. They are the same price.
In our case, the Kappara comes in place of the Cheit. Therefore it is
supposed to match it.
