Reference for Keritot 53:3

סיפא דלא הוי איל רובן קרן וחומש קרי ליה איל אשם מעילתו ויביא עמה סלע וחומשה

is exactly equal to the principal and its fifth, the Tanna implies by HIS TRESPASS his misappropriation; in the last clause, however, where the ram which he bought is not equal to the principal and its fifth, the Tanna implies by HIS TRESPASS the ram for his [Sacrilege] guilt-offering, but he must bring with it a sela' and its fifth [as restitution].

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