Halakhah sur Le Lévitique 7:25

He prohibited us from eating the forbidden fat (chelev) of a pure beast. And that is His saying, "All chelev of an ox or a sheep or a goat you shall not eat" (Leviticus 7:23). And the prohibition about it has already been repeated; and in its explanation (Leviticus 7:25), He decreed that it is [punished] with excision if one was volitional. But if he was inadvertent, he is liable for a fixed sin-offering. And the regulations of this commandment have already been explained in the first chapter of Chullin. (See Parashat Tzav; Mishneh Torah, Forbidden Foods 6.)