Rav Ashi said: “His tasting is its flaw” and “the cup of blessing requires a minimum measurement” is a single teaching. And this is what he said: what is the reason “his tasting is its flaw”? Because the cup of blessing requires a measurement and once he has tasted it, it no longer contains the full measure. Rabbi Yaakov bar Idi objected to a pitcher with a flaw; Rav Idi bar Sheisha objected to a cup with a flaw; Mar bar Rav Ashi objected even to a barrel with a flaw.
The Rabbis taught: “Remember the Sabbath day to sanctify it” — its remembrance is recited over the wine. I do not have a proof for this except for the daytime; for the nighttime, from where do I learn it? Scripture says, “Remember the Sabbath day to sanctify it”. Yes, that’s proof for the _day_, but it doesn’t answer my question: for the nighttime, from where do I learn it? It’s the other way around: the essential kiddush is is the kiddush of the nighttime, because when he sanctifies, the beginning of the day comes as the time to sanctify. And, too, at nighttime is learned from where else? Scripture says “Remember the day”.
The tanna seeks proof about the nighttime, and brings proofs from a text about the daytime! This is what he meant to say: “Remember the Sabbath day to sanctify it” — its remembrance is recited over the wine when it the Sabbath comes in.
Well, now I have no proof except for the nighttime; for the daytime, from where do I learn it? Scripture says “Remember the Sabbath day.” In the day, what should one bless? Rav Yehudah said, “… who created te fruit of the vine.” Rav Ashi visited Mechoza; they said to him: Make kiddush for us, Master, the Great Kiddush. They gave him the cup. He reasoned to himself: What do they mean “the Great Kiddush”? He said: In all the blessings, all of them, “… who created the fruit of the vine” we say at the beginning. So, he said “… who created the fruit of the vine” and paused there. He saw this elderly person lower his head and drink. He said about himself, “The wise person has eyes in his head.” a quote from Eccl. 2
The sons of Rabbi Chiyyah said: One who did not make havdallah at the departure of Shabbat may continue to make havdallah through the whole entire week. And until when? Rabbi Zeira said: Until the fourth day of the week. For Rabbi Zeira sat before Rav Assi (and some say Rav Assi before Rabbi Yochanan) and he sat and said: In the case of divorce certificates, the first day of the week, the second, and the third, are dated as following the Sabbath; the fourth and the fifth and the ascending day (i.e., the day leading into the Sabbath) are dated as preceding the Sabbath. Rav Yaakov bar Idi said: But one who has deferred saying Havdallah does not say the blessing over the light.
Rav Beruna said that Rav said: 106b One who washes his hands for motzi does not then go back and say kiddush. Rav Yitzchak bar Shmuel bar Marta said to him: Rav’s soul is not yet at rest and you are forgetting what we heard from him! Oftentimes I would stand in front of Rav; sometimes bread was more precious to him, and he would make kiddush on bread; sometimes wine was more precious to him, and he would make kiddush on wine.
Rav Huna said that Rav said: One who has already tasted food, he may not make kiddush. Rav Chana bar Chinana asked of Rav Huna: One who has tasted food, may he make havdallah? He said to him: I say one who has tasted may make havdallah, but Rav Assi said one who has tasted may not make havdallah. Rav Yirmiyah bar Abba visited the son of Rav Assi; he forgot and tasted something. They gave him a cup and he made havdallah. The wife of the son of Rav Assi’s house said to him: And did not Master rule not to do thus! He said to her, let him be, he reasons in accordance like his rabbi.
Rav Yosef said that Shmuel said: One who has tasted does not make kiddush, one who has tasted does not make havdallah.
And Rabba said that Rav Nachman said that Shmuel said: One who has tasted makes kiddush, one who has tasted makes havdallah.
Rava said: And the halacha is: one who has tasted makes kiddush, and one who has tasted makes havdallah. And one who did not make kiddush on the evening of the Sabbath may continue to make kiddush the whole entire day, until the departure of the Sabbath. One who did not make havdallah at the departure of the Sabbath may continue to make havdallah the whole entire week.