What does "be'Erkecha" mean?
Rashi: It means to the value of two Shekalim, 1 as it did in Pasuk 15.
Two Sela'im equal two Shiklei ha'Kodesh (Sifsei Chachamim).
Why does the Torah repeat "v'Hu Lo Yada"?
Rashi: To teach us that if later he discovers that he sinned, he must bring a Chatas. This is like Eglah Arufah. If the murderer was found after Arifah, he is killed.
Rashi writes that if later he discovers that he sinned, he must bring a Chatas. If so, why does he bring Asham Taluy?
Rashi (17): This shields him from punishment until he discovers that he sinned.
Rashi writes that if later he discovers that he sinned, he must bring a Chatas, similar to Eglah Arufah. Why are two verses needed, here and for Eglah Arufah?
Eglah Arufah is not brought to atone for the murderer, so we cannot learn from it to Asham Taluy. Why can we not learn a Kal v'Chomer from Asham Taluy to Eglah Arufah? Is this considered punishing from a Kal v'Chomer
Rashi writes that if later he discovers that he sinned, he must bring a Chatas. R. Eliezer (Kerisus 25a) infers that Asham Taluy is voluntary. If it were obligatory, he would be exempt later. Eglah Arufah refutes this. If the murderer was found later, he is killed!
Eglah Arufah is brought to atone for Bnei Yisrael (Devarim 21:8), and not for the murderer, therefore it does not exempt him. Asham Taluy is brought for the one who sinned, so one can say that if it were obligatory, he would be exempt later. (PF) I do not know why Moshav Zekenim left this difficult.
Why does the Torah allow a cheap Chatas, but obligates an expensive animal for Asham Taluy?
Moshav Zekenim (4:14, citing R. Yehudah ha'Chasid): Asham Taluy is to protect from punishment (until he finds out that he sinned). He is happy to spend much for it. If a Chatas were expensive, one would not examine his deeds to see whether or not he sinned. Since it is cheap, he examines, and [if he finds a Safek] brings an Asham Taluy 1 and knows for what to repent.
Perhaps he investigates, for he does not expect to find a Safek sin for which the Korban is expensive. Alternatively, the text should say 'he examines, and brings a Chatas and knows