Nobody agrees on what breaking the glass means, and that has always been true

Someone in your family has already told you the glass is about the Temple. Someone else says it means the marriage can't be undone. They're both repeating something real, and neither is the official answer, because there isn't one.

What is the glass?

Near the end of many Jewish wedding ceremonies, one or both partners step on a glass wrapped in cloth or a fabric bag, it shatters, and the room shouts "Mazel tov!" (Hebrew and Yiddish for "good fortune," used the way English uses "congratulations"). Traditionally the groom did it alone. Today it's just as often both partners together, or each stepping on their own. The whole thing takes about two seconds.

It's the most recognizable moment in a Jewish wedding, and the one couples plan least.

Where does it come from?

The oldest source is a story in the Talmud (the central compilation of rabbinic law and argument, edited by roughly 500 CE) about sages smashing expensive glassware at their sons' weddings when the celebration got too giddy. The link to the destruction of the Temple in Jerusalem came centuries later, from medieval commentators, and it's the explanation most people have heard. Other readings arrived after that and are equally in use. Jews have been arguing about this for a thousand years.

The three you'll hear most:

• The Temple. Even at the happiest moment something in the world stays broken, so the joy is never allowed to be complete.
• Joy and grief in the same room. Nobody gets one without the other, and a wedding that says so is more honest than one that doesn't.
• Irreversibility. The glass can't be put back together, and neither can this day.

The multiplicity isn't a gap in the tradition. It is the tradition. You don't have to settle which one is true, only which one you say out loud.

How do different communities do it?

Nearly every stream of Jewish practice has a version of this, and the variation is mostly about who steps on it and what gets said first. In Orthodox and most Conservative ceremonies the groom breaks it alone, at the very end, after the seven blessings (sheva brachot, the blessings said over wine near the close of the ceremony). Reform, Reconstructionist, and Renewal ceremonies routinely have both partners break it together or each break their own, with the officiant explaining it aloud beforehand. Secular and humanistic ceremonies keep it too, often with a reading that never mentions the Temple.

Orthodox ceremonies frequently pair it with a line from Psalm 137, "If I forget you, O Jerusalem." Renewal officiants often add a kavanah (an intention stated out loud before a ritual act) naming what the couple wants the moment to carry. Same-sex couples usually break one glass each, and no movement that marries them has an issue with it.

That's a description of what different rooms look like, not a ranking of them.

What do you actually step on?

A lightbulb wrapped in a cloth napkin or a fabric pouch is the most common practical answer, because it shatters under almost any shoe with a loud pop. A thin drinking glass, wrapped completely, also works. Never an unwrapped wine glass, and never lead crystal, which is thick enough to survive a stomp and turn an ankle. Kits run $15 to $60 and usually include a pouch and a keepsake vessel for the pieces.

Four things that go wrong:

• Shoes. Soft soles and thin heels don't break glass. Test at the rehearsal in the actual shoes.
• Photographers. It's over in under a second with no second take, and they miss it constantly. Tell yours when it's coming, and ask your officiant to pause visibly first. Many shoot the guests instead, since the faces are the better picture and they stay put.
• Cleanup. Assign one person to pick up the bundle immediately, especially outdoors or anywhere people might end up barefoot.
• The keepsake. Glass artists set the fragments into a mezuzah (the small case fixed to the doorpost of a Jewish home), a bowl, or jewelry, usually $80 to $400. Assign someone to collect the bundle, or a venue employee sweeps it into a bin at 11pm.

How do couples make it their own?

The three most common changes are breaking it together instead of one person doing it, having the meaning read aloud beforehand, and deciding in advance which explanation you're going to give people. All three are ordinary, and a good officiant will offer before you ask.

Both partners on one glass takes ten seconds of choreography at the rehearsal, worth doing because it's the last image of your ceremony. Two glasses, one each, skips it.

The explanation matters more than couples expect. Twenty seconds from your officiant naming which reading you chose, plus a heads-up that the response is "Mazel tov!", is the difference between a shared moment and a man stomping on something while half the room claps uncertainly. Couples who've lost a parent often pick the joy-and-grief reading and name the person.

For interfaith couples it asks nothing theologically. No blessing to say, no declaration to make, which makes it, along with the chuppah, one of the easiest Jewish elements to include when one partner didn't grow up with this.

Do you have to do it?

No. Plenty of Jewish weddings end without a glass and are complete. Couples skip it for a bad knee, a prosthetic, a venue that won't allow broken glass on the lawn, a partner who finds the Temple framing alienating, or because they don't want the loudest second of the day to be a stomp.

What people do instead, all of it normal:

• End with the seven blessings and walk out.
• End with a song, or with both sets of parents blessing the couple.
• Break something else. At tenaim (a traditional engagement agreement) it's a plate that gets broken, and a few couples borrow that instead.
• Have someone else step on it if neither of you wants to.
• Say the thing you would have said about the glass, and skip the glass.

If your family expects it and you don't, that's a conversation, not a rule, and the right officiant will help you have it rather than talk you into something. Ask how they'd handle it when you're interviewing. Listings like officiants in New York City are a place to start.