Negative commandment · Lo Ta’aseh #102 of 613
Not to place olive oil on the meal offering brought by a sinner
שלא ליתן שמן זית במנחת חוטא
The verse · Vayikra 5:11
וְאִם־לֹא תַשִּׂיג יָדוֹ לִשְׁתֵּי תֹרִים אוֹ לִשְׁנֵי בְנֵי־יוֹנָה וְהֵבִיא אֶת־קׇרְבָּנוֹ אֲשֶׁר חָטָא עֲשִׂירִת הָאֵפָה סֹלֶת לְחַטָּאת לֹא־יָשִׂים עָלֶיהָ שֶׁמֶן וְלֹא־יִתֵּן עָלֶיהָ לְבֹנָה כִּי חַטָּאת הִוא
“But if he be not able to bring two turtledoves, or two young pigeons, then he that sinned shall bring for his offering the tenth part of an efa of fine flour for a sin offering; he shall put no oil upon it, neither shall he put any frankincense upon it: for it is a sin offering.”
The Rambam’s words
Not to place olive oil on the meal offering brought by a sinner, as [Leviticus 5:11] states: "Do not place oil upon it."
שלא ליתן שמן זית במנחת חוטא, שנאמר "לא ישים עליה שמן" (ויקרא ה,יא).
Why · Sefer HaChinuch #125
To not place olive oil in the meal-offering of a sinner
“It is from the roots of the commandment [that it is] because oil is a hint for stature and greatness — since if you mix it with any liquid, it floats above them all; and it is a very significant thing.”
Who & when
“And [it] is practiced at the time of the [Temple] by the males of the priesthood, as the service is theirs.”
Where in the Mishneh Torah
Hilchot Sacrificial Procedure הלכות מעשה הקרבנות