The Fifth Cup of Wine
In the sichah which follows, the Rebbe offers a unique analysis of a halachic question that has slipped by the eyes of many commentaries.
We all know of the four cups of wine, but the Rambam and others mentioned a fifth cup. What is the source for this practice? How should it be observed? These are some of the questions which the Rebbe raises - and resolves - in the distinct way in which he treats subjects in Nigleh, the revealed realm of Torah law.
In the context of his explanations, the Rebbe also focuses on the cup of Eliyahu, a practice instituted as an expression of our faith in Eliyahu's arrival as herald of the Redemption.
May we witness his coming soon, and the ultimate peak of the Era of the Redemption, when "those who repose in the dust will arise and sing."
Sichos In English
13 Nissan, 5755
Four or Five?
Before He redeemed the Jewish people from Egypt, G-d promised Moshe:  "I will release you from the Egyptian bondship, I will save you from their hard labor, I will redeem you with an outstretched arm..., and I will take you as My nation.... And I will bring you to the land which I swore to your ancestors."
The standard text of the Jerusalem Talmud  refers to the first four of these promises as "the four promises of redemption" and explains that they are the source for the four cups of wine we drink at the Seder on Pesach.
There is, however, an alternate version of that text which also considers "I will bring you..." as a promise of redemption, bringing the number to five. And accordingly, that version speaks of drinking five cups of wine.
Similarly, in the Bablyonian Talmud, although the standard published text mentions only four cups of wine, the version of Pesachim 118a possessed by the Geonim  which states: " 'On the fifth cup, one should recite the Great Hallel,' these are the words of Rabbi Tarfon."
This difference of opinion was perpetuated in later generations.
Thus when outlining the procedure of the Seder in the final chapter of Hilchos Chametz U'Matzah, the Rambam states:  Afterwards, he washes his hands and recites the grace after meals over a third cup [of wine], and drinks it.
Afterwards, he pours out a fourth cup of wine, and completes the Hallel over it, reciting upon it the blessing of song... then he recites the blessing borei pri hagefen, [and drinks the wine]. Afterwards he should not taste anything the entire night except water.
One may pour a fifth cup and recite the Great Hallel over it, i.e., from "Praise G-d, for He is good,"  until "By the waters of Babylon."
This cup is not an obligation like the other cups. The source for this custom is the version of Pesachim 118a possessed by the Geonim  which states: " 'On the fifth cup, one should recite the Great Hallel,' these are the words of Rabbi Tarfon."
Defining the Rambam's Conception
In his gloss to the Mishneh Torah, Rabbeinu Manoach states: "From this, one can infer that it is forbidden to drink wine after drinking the four cups. For if one would surmise that it is permitted, why must one recite the Great Hallel over [the fifth cup]?
"Instead, implied is that one should not drink [another cup]. But if one desires to drink one must recite over that cup songs of praise related to the exodus of Egypt, as one recites over the fourth cup. Otherwise, it is forbidden for one to drink."
Rabbeinu Manoach's statements imply that the Rambam considers the fifth cup as optional; if a person desires to drink a fifth cup of wine, he must do so under these conditions. It appears, however, that the matter is left totally to the person's own decision. 
It is difficult to reconcile such a conception with the wording employed by the Rambam: "This cup is not an obligation like the other cups." Implied is that there is an obligation to drink a fifth cup, merely that this obligation is not as powerful as that concerning the other four cups. 
Pouring, But Not Drinking the Fifth Cup
Upon deeper consideration, the Rambam's approach can be appreciated from a careful analysis of the wording he uses.
When referring to each of the four cups of wine, the Rambam mentions specifically, "recit[ing] the blessing borei pri hagefen and drink[ing] the cup [of wine]." 
With regard to the fifth cup, by contrast, he speaks of "pour[ing] the fifth cup and reciting the Great Hallel over it" without mentioning the recitation of the blessing or the drinking the cup of wine. And if one looks again at the wording he uses, it is obvious why.
Directly before mentioning the fifth cup, the Rambam states: "He should not taste anything the entire night except water." After stating that a person should not drink anything but water after drinking t he fourth cup, the Rambam would not say that one may drink a fifth cup.
What then is the Rambam saying? That we may pour out a fifth cup, recite the Great Hallel over it, and then pour it back without drinking from it.
We find parallels in other situations. For example, when one begins a meal on Friday, finishes eating before sunset, but does not recite grace until after sunset, one may recite grace over a cup of wine. It is, however, forbidden to drink from that cup of wine until after Kiddush is recited.  In this and other instances, we see that significance is granted to recited prayers over wine, even though that wine is not drunken.
Rabbi Tarfon's Rationale
What is the rationale for such a ruling? It is possible to say that Rabbi Tarfon differs with the Sages who require four cups to be drunk.
Thus on one hand, it appears that the halachah follows the opinion which requires four cups and forbids drinking any more.
On the other hand, the fact that the Talmud discusses and debates Rabbi Tarfon's view indicates that it is given a certain degree of importance.
How then should one conduct himself?
Since the majority opinion forbids drinking more than four cups, that opinion is followed, and one drinks only four cups. On the other hand, in deference to Rabbi Tarfon's opinion, a fifth cup is poured out, the Great Hallel is recited over it, but as stated above, it is not drunken in compliance with the view that drinking it is prohibited.
Alternatively, it can be explained that Rabbi Tarfon himself does not speak of drinking the fifth cup.
To refer to the wording in the version of the Talmud cited previously: "On the fifth cup, one should recite the Great Hallel." No mention is made of drinking it. For there is a distinction between the fifth cup and the other four cups.
Each of the other four cups of wine is connected with a blessing that plays an integral part in the Seder:
The first cup is associated with the blessing of the Kiddush.
The second cup is connected with the blessing asher gealanu, which concludes the first part of the Haggadah.
The third cup is connected with the grace after meals, and the fourth cup with the blessing of song that concludes the Haggadah.
The fifth cup, by contrast, even according to Rabbi Tarfon, is not connected with a particular blessing, or any specific phase in the Seder. And therefore, it is of a different nature, and one does not drink it.
There are those  who associate the fifth cup with the cup poured for the prophet Eliyahu.
They explain that since there is an unresolved Talmudic question regarding the matter, a cup is poured out for Eliyahu, regarding whom it is said:  "The Tishbite will resolve questions and difficulties," i.e., in the Era of the Redemption, when Eliyahu will resolve all the questions of Jewish law left open throughout the centuries, he will also resolve the questions regarding this cup of wine.
Notwithstanding the cleverness of this interpretation, when a discerning look is taken at this issue, it becomes obvious that the two subjects are distinct in nature.
With regard to the fifth cup of wine, the Shulchan Aruch HaRav  summarizes the different opinions mentioned above, and rules: "From the early generations onward, it has become the universally accepted Jewish custom not to drink wine after [having drunk] four cups.... Others forbid drinking any beverage.... Their words should be heeded unless there is a dire necessity.... [In such an instance,] if no other beverages are available, only wine, a fifth cup [of wine] is permitted to be drunken, provided the Great Hallel is recited."
With regard to the cup of Eliyahu, a custom not mentioned by the Rambam, but rather originated by the Ashkenazic community,  the Shulchan Aruch HaRav writes:  "It is customary in these countries to pour out another cup of wine, besides those poured for those attending [the Seder]. This is called the cup of Eliyahu the prophet."
From the fact that the two practices are mentioned in separate sections of the Shulchan Aruch and in different contexts, it would appear that they are discrete entities. 
This is also reflected by the fact that Ashkenazic practice regards the fifth cup as permitted only in situations of necessity, but in such situations grants this leniency to every individual.
The cup of Eliyahu, by contrast, is a universal practice, but is not related to any particular individual. Instead, one cup is poured for every household.
The Soul of the Mitzvah
Every practice mandated by Nigleh, the revealed tradition of Torah law, has its parallel in P'nimiyus HaTorah, the mystic dimension of the Torah which guides our spiritual development.
In general, our Divine service is associated with four levels, corresponding to the four letters of G-d's name Yud-Heh-Vav-Heh. These spiritual rungs can be achieved by our service. The fifth cup is associated with a fifth level, a transcendent peak that cannot be attained through any mortal initiative.
Nevertheless, when a person has consummated the four levels of Divine service that depend on his efforts, he creates a suitable spiritual setting for the revelation of the fifth level.  This level is associated with the fifth cup of wine.
Since this refers to an advanced rung of spiritual accomplishment, as a whole, this endeavor is above the scope of people in our age of spiritual darkness. Therefore, this practice is not the prevalent custom in the present age.
The cup of Eliyahu, by contrast, has a future orientation. It was instituted as an expression of our faith in the coming of Mashiach and Eliyahu's arrival as his herald. This faith is present in every Jew, and indeed is given more powerful expression in the present generation described as ikvesa diMeshicha, the age when Mashiach's approaching footsteps can be heard. For as we draw closer to the Era of the Redemption, the faith in the coming of Mashiach has intensified. As such, the cup of Eliyahu is a universally accepted practice showing our eagerness to hear the herald's announcement that the time of our redemption has come.
Adapted from Likkutei Sichos, Vol. XXVII, p. 48
- (Back to text) Shmos 6:6-8.
- (Back to text) Pesachim 10:1.
- (Back to text) Cited by Rabbenu Yitzchak Alfasi. The version of the beraisa stated in our texts of the Talmud is "On the fourth cup,..."
- (Back to text) Mishneh Torah, Hilchos Chametz U'Matzah 8:10.
- (Back to text) Tehillim, psalm 136.
- (Back to text) Cited by Rabbeinu Yitzchak Alfasi. The version of the beraisa stated in our texts of the Talmud is "On the fourth cup,..."
- (Back to text) See also the Tur (Orach Chayim 481) which quotes a question posed to Rav Saadia Gaon: "If one desires to drink a fifth cup...."
- (Back to text) Rabbeinu Nissim mentions two opinions regarding the fifth cup. According to the second opinion, it is a mitzvah min hamuvchar, "the most choice way of observing the mitzvah," to drink five cups, indicating that it is preferable to drink five cups.
The Rambam does not subscribe to the view quoted by Rabbeinu Nissim, for he does not use the expression mitzvah min hamuvchar. There is, however, an association between these two conceptions. Note also the Ra'avad's notes to Rabbeinu Yitzchak Alfasi's Halachos which state that "it is a mitzvah" to follow Rabbi Tarfon's view.
- (Back to text) Hilchos Chametz U'Matzah 8:1,5, and 10.
- (Back to text) Tur and Shulchan Aruch (Orach Chayim 271:6); see also Mishneh Torah, Hilchos Shabbos 29:13.
- (Back to text) Ta'amei HaMinhagim, sec. 551, mentions this concept in the name of the Vilna Gaon.
- (Back to text) Tosafos Yom Tov and of tractate Edius; Shelah 409a.
- (Back to text) Shulchan Aruch HaRav 481, based on the Ramah.
- (Back to text) See the Haggadah of the Maharil, and the Chok Yaakov 480:6.
- (Back to text) 480:8.
- (Back to text) The association of the two practices is also made in the Haggadah of the Maharil. Nevertheless, according to the Rambam's conception, and according to the development of the concepts in the works of the Halachists, it is obvious that they are distinct issues.
- (Back to text) [To quote a like, but not identical concept: We are commanded (Vayikra 23:16) to count fifty days of the Omer. In practice, we count only forty-nine, the fiftieth day being the holiday of Shavuos.
In Chassidus (Sichos Acharon Shel Pesach, 5751), it is explained that forty-nine equals seven times seven, i.e., it refers to the full range of our emotional qualities that which are structured as a set of seven, each one including the other.
These qualities are within our potential - and hence, we have the responsibility - to refine and elevate. After we have accomplished this endeavor and created a proper setting, the fiftieth level, a sublime peak identified with the fiftieth gate of understanding, is revealed from above.]