Megillah 21A

מה משפט ביום ⁠— אף כאן ביום.

Just as judgment may be done only by day, so too here, the sota is given the bitter waters to drink only by day.

ולעריפת העגלה, אמרי דבי רבי ינאי: כפרה כתיב בה, כקדשים. ולטהרת מצורע, דכתיב: ״זאת תהיה תורת המצורע ביום טהרתו״.

And daytime is the time for breaking the neck of the heifer, as the rabbis of the school of R' Yannai said: Atonement is written with regard to the heifer, teaching that it is treated like sacred offerings, and it has already been established that all actions relating to offerings must be performed during the day. And for purifying the metzora, it is derived as it is written: “This should be the law of the metzora on the day of his cleansing” (Leviticus 14:2).

כל הלילה כשר לקצירת העומר וכו׳, דאמר מר: קצירה וספירה ⁠— בלילה, והבאה ⁠— ביום. ולהקטר חלבים ואברים, דכתיב: ״כל הלילה עד הבוקר״.

It was taught in the Mishnah: “The entire night is a valid time for reaping the omer,” as the Master said in tractate Menaḥot: The reaping of the omer and the counting of the omer must be performed at night, whereas bringing the omer offering to the Temple must be done during the day. And for burning the fats and limbs of the offerings, it is derived as it is written with regard to them: “Which should be burning upon the altar all night until the morning” (Leviticus 6:2).

זה הכלל: דבר שמצותו ביום ⁠— כשר כל היום. זה הכלל לאתויי מאי? לאתויי סידור בזיכין וסלוק בזיכין,

§ The Mishnah states: This is the principle: Something that it is a mitzva to perform during the day is valid if performed any time during the entire day. The Talmud asks: As the Mishnah has seemingly mentioned all daytime mitzvot explicitly, the words: This is the principle, are to add what? The Talmud answers: This principle comes to include the arranging of the vessels of frankincense alongside the showbread in the Temple, and the removal of those vessels at the end of the week, as the verse does not specify the time when these procedures should be performed.