Zevachim 41B

אבל יותרת ושתי כליות ⁠– דלא כתיבן בגופיה, אימא לא; קא משמע לן.

But with regard to the burning of the diaphragm and the two kidneys, which are not written with regard to the bull for an unwitting communal sin itself, you might say that this halakha should not be derived from it. Therefore, this additional derivation of “their sin offering” teaches us that the two offerings are similar with regard to this detail as well.

אמר ליה רב הונא בריה דרב נתן לרב פפא: והא תנא ⁠– פר יום הכפורים לכל מה שאמר בענין קאמר! תנאי היא; תנא דבי רב מרבי הכי, תנא דבי רבי ישמעאל לא מרבי הכי.

Rav Huna, son of Rav Natan, said to Rav Pappa: But the tanna said: “With the bull”; this serves to include the bull of Yom Kippur for all that is stated in this matter. This statement indicates that all the details applying to the bull for an unwitting communal sin are extended to the bull of Yom Kippur by means of a single derivation. Rav Pappa responded: This issue is a dispute between tanna’im, as the tanna of the school of Rav amplifies the halakha through this juxtaposition, whereas the tanna of the school of R' Yishmael does not amplify the halakha through this juxtaposition, but maintains that an additional derivation is necessary with regard to the diaphragm and the two kidneys.

תנא דבי רבי ישמעאל: מפני מה נאמרו יותרת ושתי כליות בפר כהן משיח, ולא נאמרו בפר העלם דבר של צבור? משל למלך בשר ודם שזעם על אוהבו, ומיעט בסרחונו מפני חיבתו.

§ The Talmud cites a statement that is related to the above halakhot. The school of R' Yishmael taught: For what reason are the diaphragm and the two kidneys stated with regard to the bull for an unwitting sin of the anointed priest, and they are not explicitly stated with regard to the bull for an unwitting communal sin? This can be explained by a parable: It can be compared to a flesh-and-blood king who grew angry with his beloved servant for his misdeeds, but spoke little of the servant’s offense due to his great affection for him. Likewise, as the Jewish people are beloved by God, the Torah does not describe their sin offering in detail.