This article is not intended to decide halachic questions, but rather to clarify them in a clear and concise form. Please refer all your practical questions to your local Rabbi.

Drinking on Purim "until one does not know (ad d'lo yoda) the difference between 'cursed is Homon' and blessed is Mordechai'"

The Obligation of Ad D'loi Yoda

The Gemora (Megillah 7b) quotes Rovo that "one is obligated liv'sumi [Rashi - to become intoxicated with wine] on Purim ad d'loi yoda [until one cannot distinguish] between 'cursed is Homon' and 'blessed is Mordechai'". The Gemora then relates that Rabbo and Reb Zeira once had the Purim meal together and became intoxicated. Rabbo rose and slaughtered Reb Zeira. The following day Rabbo prayed for Divine mercy and Reb Zeira came back to life. The following year Rabbo again invited Reb Zeira for the Purim meal. Reb Zeira refused explaining that one cannot expect miracles at all times. The authorities argue as to whether the halacha is in accordance with Rovo's ruling, that one should become intoxicated on Purim.

Rabbeinu Efraim [1] contends that the story of Rabbo and Reb Zeira is cited by the Gemora to show that Rovo's opinion was rejected. However, most authorities, including the Mechaber and Remo [2], rule in accordance with Rovo. (The Maharil [3], it should be noted, rules that it is desirable, rather than there being a formal obligation, to become intoxicated.)

Quantifying Ad D'loi Yoda

The Bach [4] states that according to the Tur one is literally required to become so intoxicated on Purim that one is unable to distinguish any difference between 'cursed is Homon' and 'blessed is Mordechai'. Rabbo must have reached that stage to slaughter Reb Zeira.

The Shelo Hakodoish [5] and Chacham Tzvi [6] are said to have fulfilled Rovo's ruling literally. The Shelo Hakodoish is also quoted as stating that one who is frail by nature is exempt from becoming intoxicated - the implication being that one who is fit and healthy is obligated to become intoxicated.

The Beis Yoseph [8], however, based on Tosfos [9], suggests that Rovo's requirement is abbreviated by the Gemora. In full it is that one should become intoxicated to the extent that one is unable to recite the hymn "cursed is Homon, blessed is Mordechai, cursed is Zeresh, blessed is Esther, cursed are all the wicked, blessed are the Jews" (as found in Shoshanas Yaacov). One would be unable to reach a stage where one thought that 'cursed is Homon' and 'blessed is Mordechai' were the same thing even after consuming a vast quantity of alcohol. Accordingly, Rovo's statement is not to be taken literally.

The Aguda, cited by the Mogen Avrohom [10] as halacha, states that one should be intoxicated to the extent that one is unable to calculate the gematrios (numerical values) of "orur homon" (cursed is Homon) and "boruch Mordechai" (blessed is Mordechai) which both add up to 502.

The Rambam [11] rules that one should take wine to the stage that one becomes intoxicated and falls asleep.

The Kol Bo [12] states that becoming intoxicated is a definite prohibition as it may lead to other aveiros. He rules that one should drink a little extra than usual in order to increase in making the poor joyful and comforted.

The Sfas Emes [13] explains that the obligation of ad d'lo yoda is a requirement to rejoice and drink continually: not that one is required to actually reach the stage of ad d'lo yoda; but if and when one were to reach that stage, one would be exempt from further drinking.

The Remo [14] writes that there are those who maintain that one need not become intoxicated but one should drink more than usual and sleep: once asleep one is unable to distinguish between 'cursed is Homon' and 'blessed is Mordechai'.

The Mikro'ei Koidesh [15] describes as mistaken those who explain that the Remo to be saying two things: that one need not become intoxicated but only drink more than usual, and that ad d'lo yoda can also be fulfilled by sleeping - even if one were to sleep before drinking. Rather the Remo is stating that one should sleep as a result of drinking.

The Pri Megodim [16] and Mishna Brura [17] rule in accordance with the Remo. The Mishna Brura adds that it is better not to become intoxicated if it could affect one's observance of other mitzvos, such as davening or birkas hamozon (grace after meals).

The Reason for the Obligation and the Types of Alcoholic Beverages Required

Notwithstanding the fact that intoxication is shown in the Torah in many places (such as with Noach and Lot) to have undesirable consequences, the Avudraham [18] explains that the reason for becoming intoxicated on Purim is that the miracles of Purim came about through feasting and intoxication. The downfall of both Vashti and Homon occurred at feasts of wine (mishtei yayin) and Achashverosh made a feast for Esther when she became queen. It was therefore instituted that one recall these miracles by becoming intoxicated.

R. Yosef Misaragossa [19], a student of the Ran, explains that in all mitzvos which recall some event or item, such as Pesach where matzos recall that the dough did not rise, and Succos in connection with which it is written "For I kept the Bnei Yisroel within succos..." we find the Torah stressed that particular item. For through pondering the item we recall the miracle.

Similarly with Purim (which involved a greater miracle than the exodus from Egypt in that we were saved from death to life and not just from slavery to freedom), the act of drinking excessively serves to recall the great miracle, that came about through feasts of wine.

For this reason a number of later authorities [20] rule accordingly that the mitzva of becoming intoxicated is specifically with wine. Already Rashi [21], the Rambam [22] and the Rokeach [23], had stipulated that wine should be used for this purpose although the Gilyonei Hashas [24] writes that he is unclear as to why wine in particular should be required and not any alcoholic beverage.

The Mikro'ei Koidesh provides a further reason for drinking wine on Purim - namely, that Purim needs to be a time of rejoicing - the rejoicing is through wine, as it states "wine gladdens the heart of man" (Tehillim 104).

Indeed the Gilyonei Hashas [25] states that when the Beis Hamikdosh is not standing the only way to rejoice is with wine.

The Shevilei Dovid [26], however, rules that since there is no explicit mention of wine in the Megillah, other principal alcoholic beverages are acceptable to achieve this rejoicing.

Are Women Obligated?

Women are obligated to hear the Megillah and to rejoice and partake of a festive meal on Purim, for they were part of the miracle. As far as ad d'loi yoda, however, the Rivevois Ephraim [27] and others rule that it is inappropriate for women to become intoxicated.

Indeed the Mishna Brura [28], in the laws of birkas hamazon, explains that the reason women are not obligated to make a mezuman (say birkas hamazon in a group) is that a mezuman should ideally be performed on a cup of wine and it is unseemly for a woman to do this.

When to Fulfil Ad D'loi Yoda

The Purim meal must be in the daytime, as the Megillah states, "days of feasting and rejoicing". Accordingly, Rovo [29] in the Gemoro rules that one who has the feast of Purim at night has not fulfilled one's obligation.

The Remo [30] states that the most of the meal must be completed in daylight hours, contrary to those who begin the meal close to nightfall. Accordingly the Remo writes that when Purim falls on Friday the meal may and should be eaten in the morning for the sake of the honour of Shabbos; and indeed one is permitted always to have the Purim meal in the morning if one so wishes.

The Rambam [31], after ruling that the Purim meal should be as sumptuous as one can afford, states that one should be sufficiently intoxicated so as to fall asleep. The implication is that the drinking and the consequent falling asleep are essentially connected with the feast and therefore also have to be in the daytime.

Further evidence that the drinking is connected to the Purim meal is deduced by Hisorerus Tshuva [32], from the story of Rabbo and Reb Zeira in the Gemora. Reb Zeira refused to attend Rabbo's Purim meal the following year because he was concerned that they would become intoxicated and Rabbo would slaughter him again. If the drinking were not essentially connected with the meal, it would have been safe for Reb Zeira to have the feast with Rabbo and to drink elsewhere. The fact that Reb Zeira refused to join Rabbo for the feast suggests that the drinking had to take place at the feast.

Footnotes:

1. Mentioned in Hamor Hakoton ibid 
2. Orach Chayim 695:2 
3. Ch.56 
4. 695 
5. see Sha'arei Teshuvo 695:2 
6. Siddur Ya'avetz 
7. Sha'arei Teshuvo ibid 
8. 695 
9. Megilla 7b 
10. 695:3 
11. Hilchos Megilla 2:15 
12. Hilchos Purim 
13. On the Gemorah Megilla ibid 
14. 695:2 
15. Inyonei Purim p159 
16. Mishbetzos Zohov 695:2 
17. 695:5 
18. Inyonei Purim 
19. on his commentary to Parshas Zochor p257 
20. see Mikroei Kodesh, Inyonei Purim p159; Nitei Gavriel p83 
21. Gemorro ibid 
22. ibid 
23. Ch.237 
24. on Megilla ibid 
25. Pesachim 109a 
26. Orach Chayim 695:3 
27. Vol.1 Ch.161 
28. Orach Chayim 199:6, in Sha'ar HaTzion 
29. ibid 
30. ibid 
31. ibid 
32. Vol I, Ch.6