The 73rd prohibition is that we are forbidden from either entering the Temple grounds or giving a legal decision in any law of the Torah when intoxicated.
The source of this prohibition is G‑d's statement1 (exalted be He), "You [and your descendants] may not drink wine or any other intoxicant when you enter the ohel moed ...or when you render legal decisions for the Jewish people...." In the words of the Talmud,2 "If he drank a revi'is,3 he may not render a decision."
The punishment for violating this commandment varies according to the circumstances. One who drank wine may not enter the area between the entrance hall (ulam) and the altar or into the sanctuary itself (heichal); if he did so, the punishment is lashes. If he performed the Temple service when intoxicated, he receives misah bidei Shamayim (a Heavenly death sentence). If he drank something intoxicating other than wine4 and performed Temple service, his punishment is lashes rather than death. One who offers a legal decision when intoxicated also violates this prohibition, whether he is a kohen or non-kohen; whether intoxicated from wine or some other intoxicant.
The Sifra states [this distinction in punishments]: "From the words 'You may not drink wine' I know only that wine is forbidden. What is the source for prohibiting other intoxicants? It is the word v'sheichar ['or any other intoxicant']. If so, why is wine mentioned separately? [To indicate that it has a different punishment —] for wine one is punished by death, and for other intoxicants it is only a prohibition [punished by lashes]."
There [in the Sifra] our Sages also say, "What is the source for the law that one is punished [by death] only when performing the Temple service? It is the verse,5 'You and your descendants [may not drink wine or any other intoxicant] when you enter the ohel moed [— otherwise you will die.]' "6
There [in the Sifra] our Sages also say, "You might think that non-kohanim are punished by death for rendering legal decisions [when intoxicated] — therefore the verse says that 'You and your descendants...otherwise you will die.' You and your descendants [i.e., kohanim] are punished by death [for performing service], but non-kohanim are not punished by death for rendering legal decisions [while intoxicated]."
The details of this mitzvah are explained in the 4th chapter of tractate Kerisus.7
