Sefer HaChinuch ספר החינוך

The commandment of the sanctification of Shabbat with words: To speak words on the Shabbat upon its entry and also its departure — that there be in them cognizance of the greatness of the day and its stature and its positive distinction from the other days before it and after it; as it is stated (Exodus 20:8), “Remember the Shabbat day, to sanctify it,” meaning to say, remember it with a memory of [its] holiness and greatness. And in explanation, our Sages told us (Pesachim 110a) that we are commanded to say these things upon wine — as so does the explanation come: remember it over wine. And the content is that we place into a cup a revi’it or more of pure or mixed wine — but not less than this (Pesachim 108b). And it is known that the [proportions of the] mixture is one part pure good wine to three parts water. And we recite the blessing of the Kiddush (sanctification) of Shabbat upon it, according to the wording that is known among the Jews. And so [too], at the departure of Shabbat, we recite the blessing over the wine in honor of the day — and that blessing of the conclusion of Shabbat is called Havdalah (Berakhot 52a).

It is from the roots of this commandment [that it is] in order that we be aroused through this act to remember the greatness of the day and that we fix upon our hearts faith in the creation of the world, “that in six days the Lord made, etc.” (Exodus 20:11). And therefore, we are obligated to do an act with wine — since the nature of man is to be greatly aroused by it (Berakhot 35b), as it satiates and causes joy. And I have already said to you that according to the arousal of a man and his acts will he always be acted upon towards things. And from this root did they, may their memory be blessed, say in the Gemara (Pesachim 106b), that if bread is more beloved to a person, he should sanctify [the day] over bread — since then his nature will be more aroused by that which he craves. And even though in the departure of the day, they did not say this, but rather obligated him to recite Havdalah with wine nonetheless, they were correct with this as well; since they, may their memory be blessed, as well as the perfect Torah, will always choose to go according to the majority. And in truth, the majority of the world will desire drinking over eating at the conclusion of Shabbat; since they have already [eaten] a large meal during the day in honor of the Shabbat. And there is no need to give a reason for their obligating us that there be a revi’it of wine in the cup; since less than this amount is not fitting and will not arouse the heart of a man upon it. And that which they obligated us in rinsing the cup (Berakhot 51a), and not to drink anything until he recites the Kiddush (Pesachim 105a) and that he recites the Kiddush at the location of his meal — all of [these] are branches of the root of arousal that I [discussed].

The laws of the commandment — for example, which is the wording of the Kiddush and the Havdalah; which wine is fitting to recite upon the Kiddush and which is not (Bava Batra 97a); if we sanctify or recite Havdalah over ale (Pesachim 107a); one who eats on the eve of Shabbat and the Shabbat [begins] (Pesachim 100a), or on Shabbat and Shabbat departs; so [too] the wording of the Kiddush and Havdalah of holidays; the laws of the blessings we are obligated to recite upon the candle on the conclusion of Shabbat and Yom Kippur; the laws of the blessing that we are obligated to recite over the spices and which spices are fitting to bless upon them or not fitting (Berakhot 51b); and the rest of its details — are [all] elucidated at the end of Pesachim and in places in Berakhot. (See Tur, Orach Chaim 262, 271.)

And [it] is practiced in every place and at all times by males and females — even though it is from the commandments that is caused by time (from which women are generally exempt). As so did our Rabbis, may their memory be blessed, teach us (Berakhot 20b) that women are obligated in Kiddush and Havdalah. And one who transgresses it and does not perform the Kiddush with words has nullified this positive commandment. And if he performs the Kiddush with words without wine and without bread, he has fulfilled it ex post facto [according to] the Torah.