Midrash su Levitico 23:32

4) (Vayikra 23:29) "For every soul which will not be afflicted on this self-same day will be cut off from its people." This is the punishment for (non-) application. (Vayikra 23:30) "I shall make that soul go lost": What is the intent of this? (i.e., What do we learn from this equivalence between kareth ["cutting-off"] and "aveidah" ["going lost"]?) Because "kareth" is mentioned in every place and I do not know what it is, "I shall make that soul go lost" indicates that "kareth" refers to complete destruction (and not merely to the cutting off of the soul from the body.) And whence is it derived that eating, drinking, washing, anointing, cohabitation, and shodding are forbidden on Yom Kippur? From (Vayikra 23:32) "A Sabbath of resting … and you shall afflict" (The connotation is extension of affliction). I might then think that all of these are forbidden on the Sabbath of creation (i.e., Saturday, which is also referred to as "a Sabbath of resting"); it is, therefore, written "A Sabbath of resting it (Yom Kippur) shall be for you and you shall afflict, etc." "It" is forbidden in all (of these things), and not the Sabbath of creation.

5) (Vayikra 23:32) ("and you shall afflict your souls on the ninth day of the month in the evening; from evening until evening shall you rest your resting.") I might think that he should fast on the ninth day itself; it is, therefore, written "in the evening." If "in the evening," I might think when it became dark; it is, therefore, written "and you shall afflict your souls "on the ninth." How is this to be resolved? He begins fasting (on the ninth) when it is still light, adding "from the profane to the holy." This tells me (that we add) only before. Whence do we derive the same ("adding") for after? From "from evening until evening."

(Ib. b) We are taught: R. Eliezer says: "A man shall do nothing else on a holy day, but either eat and drink or sit and study." R. Joshua says: "A man must divide the holy day, one-half to be spent in eating and drinking, and the other half [in learning] at the house of study." "Both," said R. Jochanan, "make their deductions from the same passages. One passage says (Deu. 16, 8) A solemn assembly to the Lord, thy God, and another passage says (Num. 29, 35) 'Have ye' a solemn assembly. [How can both of these passages be reconciled? If it is to be solemn to 'the Lord,' then why say 'have ye'?] R. Eliezer, therefore, is of the opinion that this intends to suggest a celebration either for God or for yourself;" but R. Joshua is of the opinion that it means to divide the day, one-half for God and one-half for yourself." R. Eliezer said: "All agree that on the Shebouth festival, a certain part should also be devoted for yourself, because it is the day on which the Torah was given [hence we ought to rejoice on that occasion]." Rabba said: "All agree that the Sabbath should also be devoted for yourself. The reason of it is (Is. 58, 13) And thou shalt call the Sabbath rejoicing." R. Joseph said: "All agree that Purim should also be devoted for yourself; explanation is found in (Esther 9, 22) days of feasts and rejoicing." Mar, the son of Rabina, used to fast the whole year round except on Shebuoth (Feast of Weeks), Purim (Feast of Esther) and the day preceding Yom Kippur (Day of Atonement); on Shebuoth, being the day Israel received the Torah; Purim, concerning which it is written (Est. 9, 22) … days of feast and rejoicing; the day preceding Yom Kippur, because R. Chiya b. Rab, of Difthi, recited: (Lev. 23, 32) And ye shall afflict yourselves on the ninth day of the month. Do we fast on the ninth day? Behold it is only on the tenth that we fast! But this means to teach us that whoever eats and drinks on the ninth. Scripture accounts to his credit, as though he had fasted on both the ninth and tenth days.