You cannot do a seder, or a Shabbat, without it. Bring the good stuff.
Wine is woven through Jewish celebration: the four cups of the Passover seder, the Kiddush that opens Shabbat and holidays, the cup under the wedding canopy. A quality kosher bottle respects the tradition and, frankly, makes the ritual more pleasant for everyone drinking it.
The old jokes about syrupy sweet kosher wine are decades out of date. Israeli and California kosher winemaking has come a long way, and there are genuinely excellent bottles across every style. Bringing one as a guest is always correct and always welcome.
Pick a good bottle, add a ribbon, and you have a host gift that says you know the occasion. For a wedding or a milestone, a nicer bottle to be opened on an anniversary turns the gift into a small tradition of its own.
Seder and Shabbat hosts, wedding couples, and anyone you are visiting for a Jewish occasion. The universal 'do not show up empty-handed' gift.
Well-stocked wine shops and kosher markets. Ask the shop for their best Israeli or California kosher bottles, the staff usually have strong opinions.