Drunkenness in the Tosefta

For what reason did they say (Ter. 1:6) that a mute cannot separate terumah? Because he cannot bless. For what reason did they say that a blind person cannot separate terumah? Because he cannot distinguish between good and bad [produce]. For what reason did they say that a drunk person cannot separate terumah? Because he has no understanding. [However,] even though he is drunk, his purchases are [valid] purchases and his sales are [valid] sales, and his gifts are [valid] gifts, and his vows are [valid] vows, [and] his sanctified property is [valid] sanctified property, [and] his transgressions are [punishable] transgressions, [and] if he is held liable for sin-offering then he must bring a sin-offering, and [if he is] held liable for stoning he is stoned.

The general rule of the matter is that a drunk -- behold -- he is like someone who is sober in every respect.

For what reason did they say a ba'al keri (see Zavim 5:11) cannot separate terumah? Because he cannot bless.

For what reason did they say one who is naked cannot separate terumah? Because he cannot bless. But he covers himself with straw or with stubble or with anything and he blesses.

One who has been drinking wine is invalid to perform service in the Temple and is obligated for death.

What is someone who "has been drinking wine"?

Any one who has drunk a quarter-log (about 1.5 eggs-worth of volume) of wine that is forty days old or older.
If he drank more than a quarter-log of wine from his winepress, he is exempt.
If he drank less than a quarter-log of wine four or five years old, he is liable, whether he mixed it and drank it in little sips.
Rabbi Eliezer says: "If he drank it in one gulp, he is liable.

If he mixed it and drank it, or drank it in little sips, he is exempt."
Rabbi Yehudah says: "Those who transgress against the prohibition of drinking wine and serving in the Temple are subject to the death-penalty. Fermented beverages are subject to warning. Therefore, if he ate a fig from K'eilah or drank milk and honey, behold, this one is struck with forty stripes and transgresses a negative commandment."
And just as, if he was a priest, he is invalid for the Temple service and liable to the death penalty, so if he was a sage or a disciple of a sage, he is prohibited from teaching or from giving instruction.
Rabbi Yose, son of Yehudah, says: "If he was a sage, he is permitted to teach."

It so happened with Rabban Gamaliel that he was travelling from Akko to Cheziv. He found a loaf [of bread] on the road. He said to his servant Tabi, "Take this loaf." Thereafter, he saw a Gentile [and] he said to him, "Mabgai, take this loaf." Rabbi Ilai ran after [Magbai and] said to him, "Where are you from?" He said to him, "From the guard-tower villages" (see Y. Avodah Zarah I.9.3, Guggenheimer tr.). He said to him, "What is your name?" He said to him, "Magbai," He said to him, "Do you happen to know Rabban Gamaliel?" He said to him, "No." From this we learned that Rabban Gamaliel was directed by the Holy Spirit. We learned three things: We learned that the chametz of a Gentile is permitted immediately after Passover, and that one should never pass by food [without picking it up], and that we follow after the majority of the travelers on the roads. They arrived in Cheziv, and someone came and asked him about [annulling] his vow. He said to the one who was with him (i.e., Rabbi Ilai), "Did we not drink a quarter-log of Italian wine?" He said to him, "Yes." He said to him (i.e., the one seeking dissolution of his vow), "In that case, come walk with us until the wine dissipates inside of us." He walked with them until the Ladder of Tyre. Once they had arrived at the Ladder of Tyre, [Rabban Gamaliel] dismounted from his donkey, wrapped himself [in his cloak], and sat down, and dissolved his vow. And we learned many things on that day. We learned that a quarter-log of wine make one drunk, and that walking dissipates [the effect of] wine, and that one who has drunk wine should not provide instruction, and that vows are not dissolved while riding or while walking or while standing, but only while wrapped [in a cloak] and sitting.