Says the Gemara [Yoma 76b]:
אשכחן סיכה רחיצה מנא לן אמר רב זוטרא ברבי טוביה אמר קרא (תהלים קט, יח) ותבא כמים בקרבו וכשמן בעצמותיו ואימא כשתיה דומיא דשמן מה שמן מאבראי אף מים מאבראי
We have found proof that abstaining from smearing oil on oneself is considered affliction; from where do we derive that abstaining from bathing is also called affliction? Rav Zutra, son of Rabbi Toviya, said: The verse states: “And it came into his innards like water, and like oil into his bones”(Psalms 109:18). This means that the water with which one bathes and the oil with which one smears himself are absorbed into the body. Just as abstaining from smearing oil is considered an affliction, so too, abstaining from bathing is considered an affliction. The Gemara objects: But say that “came into his innards like water” is referring to drinking rather than smearing oil. The Gemara rejects this: It is similar to oil. Just as the oil described in the verse is smeared from outside the body and not drunk, so too, the water mentioned in the verse is used for bathing from the outside. It is not drunk.
והא תנא איפכא קא נסיב לה דתנן מנין לסיכה שהיא כשתיה ביום הכפורים אף על פי שאין ראיה לדבר זכר לדבר שנאמר ותבא כמים בקרבו וכשמן בעצמותיו אלא אמר רב אשי רחיצה מגופיה דקרא שמיע ליה דכתיב וסוך לא סכתי
The Gemara asks: But the tanna took the opposite meaning, as we learnedin a mishna: From where do we derive that smearing oil is like drinking on Yom Kippur? Although there is no explicit proof of the matter from the Bible, there is an allusion to the matter from the verse, as it is stated: “And it came into his innards like water, and like oil into his bones” (Psalms 109:18), meaning that oil on the body is like water within it. Therefore, the phrase “and it came into his innards like water” is referring to the act of drinking water. Rather, Rav Ashi said: Bathing is derived from the same verse cited above, as it is written: “Neither did I anoint myself at all”(Daniel 10:3). This teaches that Daniel did not do any anointing, including bathing. Consequently, the same source prohibits both of these activities.
Tosfos [77a ד"ה דתנן] write
פר"ת דכל עינויים דיוה"כ ליתנהו אלא מדרבנן וקראי אסמכתא בעלמא לבר מאכילה ושתיה
R. Tam's opinion: R. Tam explains that all of the Inuyim of Yom Kipur, except for eating and drinking, are only mid'Rabanan. The psukim are mere Asmachtos.
דהאמר לקמן ואם היה מלוכלך בטיט ובצואה רוחץ כדרכו ואינו חושש מי שיש לו חטטין בראשו סך כדרכו ואינו חושש ובמסכת כריתות בפ"ק (דף ז.) אמרינן כהן שסך שמן של תרומה (למעים) בן בתו ישראל מתעגל בו ואינו חושש
Support: Below, we say that if one was dirty with mud or excrement, he washes normally without concern. If one has scabs on his head, he anoints normally without concern. In Kerisus (7a) we say that a Kohen may anoint his daughter's son, a Yisrael, with Terumah oil, without concern.
ואי הוי דאורייתא היה אסור בכל ענין אלא מדרבנן
If it were mid'Oraisa, it would be forbidden in every case. Rather, it is mid'Rabanan.
So Tosfos holds that סיכה with תרומה on a זר is only מדרבנן. This Tosfos is a wonder for the following reason. The gemara in Krisus says as follows:
תני רב חנניה קמיה דרבא מנין לכהן גדול שנטל משמן המשחה שעל ראשו ונתן על בני מעיו מנין שהוא חייב שנאמר (שמות ל, לב) על בשר אדם לא ייסך א"ל רב אחא בריה דרבא לרב אשי מ"ש מהא דתניא כהן שסך בשמן של תרומה בן בתו ישראל מתעגל בו ואינו חושש
Rav Chananya taught a halacha before Rava: From where is it derived with regard to a High Priest who took from the anointing oil that is on his head and placed it on his stomach; from where is it derived that he is liable? It is derived from a verse, as it is stated: “Upon the flesh of a person it shall not be applied” (Exodus 30:32). Rav Acha, son of Rava, said to Rav Ashi: What is different between this case and that which is taught in a braisa: In the case of a kohen who applied teruma oil to himself, the Israelite son of his daughter may rub against [misaggel] this oil without concern that he might be deriving benefit from teruma?
א"ל התם (ויקרא כב, ט) ומתו בו כי יחללוהו כתיב כיון דחלליה הא איתחיל אבל גבי שמן המשחה כתיב (במדבר ו, ז) כי נזר גו' אלהיו עליו שמן משחה קרייה רחמנא דאע"ג דאיתא עליו לא איתחיל:
Rav Ashi said to him: There, with regard to teruma oil, it is written: “They will die through it if they profane it” (Leviticus 22:9), and since the kohen has already profaned the oil by using it, it is considered profaned. But with regard to the anointing oil it is written: “For the consecration of the anointing oil of His God is upon him” (Leviticus 21:12). The Merciful One calls it anointing oil even at this stage, to teach that even though it is upon the kohen gadol it is not considered profaned, and instead remains sacred.
If it is true that anointing with תרומה for a זר is only מדרבנן [as Tosfos asserts], then why does the Gemara ask from the case of anointing a זר with תרומה on the case of שמן המשחה?? There is a simple distinction: Anointing with שמן המשחה is מדאורייתא while doing the same with שמן תרומה is only מדרבנן?!
