Rab Judah stated in the name of Samuel: He who has drunk a quarter of a log of wine must not give a legal decision. This ruling’ observed R. Nahman, ‘is not a very fine one, because in my own case, before I drink a quarter of a log of wine my mind is not clear’.
Said Raba to him: Why did the Master speak in such a manner? Did not R. Aha b. Hanina in fact state, ‘What is the exposition of the Scriptural text: But he that keepeth company with harlots (zonah) loses his substance? (Prov. 29:3) Whosoever says: "This ruling is a fine one” (zoh na) or "That ruling is not a fine one" loses the substance of the Torah’ — ‘I withdraw’, the other replied.
See, that was a pun. Right? No? Ok, moving on. . .
Rabbah son of R. Huna ruled: One who is under the influence of drink must not pray, but if he did pray his prayer is regarded as a proper one. An intoxicated man must not pray, and if he did pray his prayer is an abomination.
How do we tell the difference? I'm glad you asked:
How are we to understand the expression of ‘One who is under the influence of drink’, and how that of ‘an intoxicated man’? — As follows. When R. Abbab. Shumani and R. Menashya b. Jeremiah of Difti were taking leave from each other at the ford of the river Yopati they suggested, ‘Let each one of us say something that the other has never heard before, for Mari son of R. Huna laid down: The best form of taking leave of a friend is to tell him a point of the halachah, because he would remember him for it’. ‘What is to be understood’, one of them began, ‘by "one who is under the influence of drink" and what by "an intoxicated man"? The former is one who is able to speak in the presence of a king, the latter is one who is unable to speak in the presence of a king’.