As long as were talking about a quarter log of wine, what other halakhot use this liquid measurements? TB Nazir 38

The Mishnah back on daf TB Nazir 34b cites the minimum amount of wine a nazir needs to drink in order to become liable for lashes because he has violated a negative prohibition. “An initial version of the mishna says that a nazirite is liable to receive lashes only if he drinks a quarter-log (revi’it-רביעת) of wine.” (Sefaria.org translation) A quarter log is approximately 2.7 ounces. Today’s daf TB Nazir 38 shares other halakhot revi’it of liquid is required. Some of them are relevant to today’s life like how much wine for each cup needs to be drunk at the Passover Seder. Some of them are no longer relevant because the Temple no longer stands and we are not permitted to observe these commandments. One is no longer relevant thanks to indoor plumbing!

“Apropos a quarter-log, the Gemara cites a statement that Rabbi Elazar says: There are ten applications of the quarter-log measurement in various areas of halakha, and Rav Kahana held in his hand the following mnemonic for them: Five are red and five are white. The Gemara elaborates: The five red ones of wine and blood are listed in the following mnemonic: A nazirite; and one who performs the ritual of the Paschal offering; who instructed; in the Temple; and they died.

“The Gemara explains this mnemonic: A nazirite, this is referring to the quarter-log of wine for which a nazirite is liable for drinking. Who performs the ritual of the Paschal offering, this is as Rav Yehuda says that Shmuel says: It is a mitzva to drink these four cups at the Passover seder and they must each contain the amount of a quarter-log. Who instructed, this is referring to the following halakha: One who drank a quarter-log of wine may not issue rulings to others in matters of halakha, lest he err. In the Temple, this is referring to the halakha that one who drank a quarter-log of wine and entered the Temple is liable to receive the death penalty (see Leviticus 10:9).

“And they died, this is as it is taught in a mishna (Oholot 2:10): From where is it derived with regard to a quarter-log of blood that emerges from two corpses, that it renders people and objects ritually impure in a tent, i.e., a house, meaning that one who enters that house contracts ritual impurity imparted by a corpse? As it is stated, with regard to the prohibition against ritual impurity for priests: “Neither shall he go in to any dead bodies” (Leviticus 21:11). The plural form indicates that the blood of two people joins together to form the minimum amount of a quarter-log for ritual impurity in a tent.

“And the five white (not necessarily white, but clear-gg) cases of oil and water are listed in this mnemonic: The loaf of, a nazirite, and a leper, which were disqualified, on Shabbat. The Gemara elaborates: The loaf of, this is referring to the quarter-log of oil added to the loaves of a thanks-offering. A nazirite, this is referring to the quarter-log of oil for the wafers of a nazirite, which were brought with his offering. A leper, this is referring to the quarter-log of spring water into which a bird is slaughtered for the ritual purification of a leper (see Leviticus 14:5).Which were disqualified, this is as we learned in a mishna (Me’ila 17b): And all other ritually impure liquids disqualify the body to the extent that one who drinks them may not eat teruma, if one drank the amount of one quarter-log.

“On Shabbat, this is as we learned in a mishna which lists the minimum amounts of various liquids for which one is liable for violating the halakhot of Shabbat for carrying them from one domain to another. At the conclusion of this list, the mishna states (Shabbat 76b): And the measure that creates liability for carrying all other liquids, those not specified in the list, is a quarter-log, and the measure for carrying all waste water is likewise a quarter-log. This completes the list of ten halakhot that feature the quarter-log.” (Sefaria.org translation)

The Gemara goes on to show that this is not an exhaustive list.

“And are there no more than ten? But there is also the following mishna (Yadayim 1:1): With a quarter-log of water one can wash the hands of one person before eating bread, and this amount can be used even for two people, if they do so in the correct manner…

“But there is this halakha concerning a sota (Sota 15b): The priest who dealt with a sota would bring an earthenware vessel [pailei] and place in it a half-log of water from the basin in the Temple, and Rabbi Yehuda says it was a quarter-log. (God’s name was written on a piece of parchment and placed in this revi’it of water. God’s name would be dissolved and the woman suspected of adultery would drink this water concoction. More about this when we learned the next massekhet entitled Sotah)…

“But there is the following halakha: How much water must one place in a vessel that contains urine, before he can pray nearby? Any quantity is sufficient. Rabbi Zakkai said: A quarter-log.” (Sefaria.org translation)

If memory serves me correctly, these types of measurements in order to fulfill one’s obligation are ancient traditions that the rabbis ascribed back to Moses received them from upon Mount Sinai.