Drinking on Rosh HaShanah

The LORD spoke to Moses, saying:

Speak to the Israelite people thus: In the seventh month, on the first day of the month, you shall observe complete rest, a sacred occasion commemorated with loud blasts.

You shall not work at your occupations; and you shall bring an offering by fire to the LORD.

In the seventh month, on the first day of the month, you shall observe a sacred occasion: you shall not work at your occupations. You shall observe it as a day when the horn is sounded.

A man is obligated to gladden his children and the members of his household on a Festival, as it is stated: “And you shall rejoice on your Festival, you, and your son, and your daughter, and your manservant, and your maidservant, and the Levite, and the stranger, and the fatherless, and the widow that are within your gates” (Deuteronomy 16:14).

With what should one make them rejoice?

Rabbi Yehudah says: "Men with what is fit for them and women with what is fit for them."

It was taught:

"When the Temple is standing, rejoicing is only through meat, as it is stated: 'And you shall sacrifice peace-offerings and you shall eat there and you shall rejoice before the Lord your God' (Deuteronomy 27:7).

And now that the Temple is not standing, there is no rejoicing, except with wine, as it is stated: 'And wine that gladdens the heart of man' (Psalms 104:15)."

Eat and drink and be happy, but do not fast either on Rosh Hashanah nor on Repentance Shabbat. However, people should not eat to the fullness of their satiety so that they do not come to levity in order that there should be awe of the Lord upon their faces.

And Rabbi Simon Luria (1510-1573) wrote that he received from his elder not to eat fish on Rosh HaShanah in order to decrease the human desire a little bit of a particular thing and remember it is Judgment Day and not to come to frivolity.

Which is to say that even though it is Judgement Day, nevertheless, there is a mitzvah of rejoicing on your holiday that is relevant to this day that it is also within the category of חג, as it is written, "Blast the horn at the new moon, at the full moon for our feast-day" (Ps. 81.4), and it is said in Nehemiah 8, "eat fatty foods and drink sweet drinks...for this day is holy unto our Lord; do not be sad, for the joy of the Lord is your strength" (Neh. 8.10).