Said Rabha: A man is obliged to intoxicate himself on Purim, till he cannot distinguish between "cursed be Haman" and "blessed be Mordecai."
— Babylonian Talmud, Book Four, Megillah, ch. 1.
A curious injunction. As Daniel Alder notes ('Drinking on Purim: When to Say When?'), you'd have to be really massively drunk not to be able to distinguish those two phrases; this fact leads him to consider less literal interpretations. One mediaeval commentator suggests that what is required is the repetition of a tongue-twister, something like "Cursed be Haman. Blessed be Mordecai. Cursed be Zeresh. Blessed be Esther", which would be a little more taxing. The famous talmudist Rashi, meanwhile, claims that the festive wine will send the reveller slumberward, thus unable in sleep to distinguish any two phrases. Yet another mediaeval, predictably, follows the gematria route, demonstrating the numeric equality of the two phrases in question. Compare another oenophilic Hebrew trick:
A simple example of gematric power might be the Hebrew proverb [nik' nas 'jajin jå' så sōd], lit. 'entered wine went out secret', i.e. 'wine brings out the truth', in vino veritas. The gematric value of יין 'wine' is 70, and this is also the gematric value of סוד 'secret'. Thus, this sentence, according to many Jews at the time, had to be true.Why would any organised religion promote pleonastic inebriation? Alder's solution is merely a celebration of communal triumph over hardship, alcoholism providing a means of overcoming rationality, in the manner of soma and Sufic whirling. Which isn't really any explanation at all. But for a different take on drunkenness, so typically Greek in its rational irony, see Plato's Laws (his last work), end of Book One. In this dialogue, the Athenian Stranger, who takes Socrates' place, argues that institutional drunkenness would test the moral resolve of young soldiers, just as gymnastics tests for physical fearlessness in peacetime:
— Ghil'ad Zuckermann, 'Language Conflict and Globalisation' (2003).
The legislator would induce fear in order to implant fearlessness; and would give rewards or punishments to those who behaved well or the reverse, under the influence of the drug?
And this mode of training, whether practised in the case of one or many, whether in solitude or in the presence of a large company—if a man have sufficient confidence in himself to drink the potion amid his boon companions, leaving off in time and not taking too much,—would be an equally good test of temperance?
Let us return to the lawgiver and say to him, 'Well, lawgiver, no such fear-producing potion has been given by God or invented by man, but there is a potion which will make men fearless.
You mean wine.
Yes; has not wine an effect the contrary of that which I was just now describing,—first mellowing and humanizing a man, and then filling him with confidence, making him ready to say or do anything?