I assume that you are referring to the breaking of the glass at the end of the marriage ceremony and the bubbe meisse. The superstition states that the breaking of a glass casts away the demons and awakens the groom to the realities of married life. But there are a lot of other explanations for the breaking of the glass, besides the bubbe meisse (superstition). It can represent the breaking of the hymen, the sorrow at the destruction of the temple (or garden of Eden) or even the Talmud's tale of Rav Ashi's son.

It is not really a superstition to my understand. In other words and like hundred others supposed superstitions, they are product of the ignorance that the followers of Judaism have from his own belief of faith. I will explain it. The Judaism and like the Christianity, both belief of faith occult the enigma of God to the mankind and them everybody ignore they are adoring a STONE without to have discernment about it; since, their religious representatives occult the Biblical God really is the Divine Constructor of Great Pyramid, in whose geometry interior you have drawing the Face of the Lion of Judah, the God of Jews in Egypt. Not matter what you see in looking the Geometry of Great Pyramid, you cannot see this Face, but if you draw a new axis at the center of the Coffer the one you have into the King's Chamber and then you duplicate at the left side from this axis that what you have at the right side... you will see the Face of the Lion of Judah, whose NOSE is cover for a VEIL (Moses), the ROCK where the Great Pyramid was raised. Do you know the Law of Retaliation? The Breaking by Breaking is the WELL SHAFT, the Subterranean Chamber or Pit of the Mine have a deep hole on the ground, in being this one the TOOTH and the Eye is the Chamber of the Queen. The Glass (MIRROR) is the new axis you drawed at the center of Coffer in ennouncing the Law of Retaliation, the reason of intelligence of why Jesuchrist didn't mention the breaking by breaking from Moses to mention that of.. if somebody hit your Right Cheek.... turn the other, the Left Cheek...! Why? Because he is talking of a FACE, the face of the Lion of Judah into the Great Pyramid. Then, by that time the Jews adored the Great Pyramid and in knowing of the prior about, they used to mention among them a masonic religious symbol... if you break the Mirror (a Glass)that show you the Face of your God, the Lion of Judah, then, you will be execrated from our belief of faith since you are denying to see the Face or God. I am so sorry my English.

The broken glass at the end of a marriage is also found in (some) Greek Orthodox churches. I always thought it was symbolic of something irreversible, but that's just my view.

Judaism is not superstitious- many Jews might be, but the religion isn't. So, Judaism doesn't believe that broken glass (even mirrors) brings bad luck. At the end of a Jewish wedding ceremony, the groom stamps on a glass and the crowd responds with a hearty "Mazal tov!" (the Jewish wish for GOOD fortune). Breaking the glass reminds the couple that our world is imperfect and that no personal joy can be complete as long as there is pain and suffering anywhere in the world. This should inspire the couple to use their special day (which Jews believe is one of the times in your life that you're closest to G-d) to pray for a better world. Also, you cannot repair a shattered glass, it's an irrevocable step. The subtle message to the newlyweds is that their commitment to each other should also be irrevocable. [And the cynics say this is the last time a married man gets to put his foot down...]

The destruction of the temples -- reminding us that even in moments of joy we have to remember the pain of loss.