'Mazal tov," cries the crowd as the glass is broken at the end of a wedding ceremony. The response is so ingrained that no matter where we are, a glass that shatters - or for that matter any dish - is immediately followed by shouts of mazal tov. In truth, joyous exclamations are a strange reaction to this custom, for we break the glass under the wedding canopy as an acknowledgment of our unredeemed state. This blissful day for the newlyweds, and indeed festive occasion for the Jewish people, is momentarily toned down as we set the fallen Jerusalem above our highest joy (see Psalms 137:5-6). Why do we seek to dull our happiness at its height? Why must we gloomily mingle our enjoyment with sadness? On the biblical verse "Serve God with awe and rejoice with trepidation" (Psalms 2:11), the Talmud explains the unusual pairing - rejoice with trepidation: "Where there is rejoicing, there should also be trepidation" (B. Berachot 30b-31a). Following on from this line, the Talmud relates that Abaye was sitting before Rabba, his teacher, when the master noticed that the student was excessively cheerful: "It is written rejoice with trepidation," reminded the teacher. The student sought to alleviate the concern: "I am wearing tefillin," implying that there was no need for concern as he was well aware of the heavenly yoke. In a similar episode, Rabbi Yirmiya was sitting before his master, Rabbi Zeira, and once again the teacher perceived that the pupil was excessively jolly: "It is written in all sorrow there is benefit" (Proverbs 14:23), recalled the teacher, using a verse that seems to advocate a cheerless disposition. The response was similar: "I am wearing tefillin." Thus the two students - Abaye and Rabbi Yirmiya - each acknowledged the dangers of excess cheer as an indicator that the heavenly yoke has been discarded. Bearing the weight of tefillin - they assured their teachers - had a sobering effect and tempered this merriment. Some commentators suggest that the students were explaining the reason for their high spirits: The opportunity of wearing tefillin led to their exuberance. Thus the teachers need not be concerned that their excitement was misplaced (Rabbeinu Yona Gerondi, Spain, 13th century). Either way, our sages appear to frown upon unrestrained joy. To buttress this contention, the talmudic passage relates three wedding tales: The sage Mar the son of Ravina made a wedding feast for his son. The host saw that his rabbinic guests were manifestly cheerful, so he brought a precious glass cup worth 400 zuz and smashed it before them. Though it is generally forbidden to destroy useful objects, where the damage is purposeful the prohibition does not apply. Here Mar sought to check the levity of his guests, and indeed succeeded as they were saddened by the loss of this valuable item. In a similar episode, Rav Ashi made a wedding feast for his son and when he perceived that his colleagues were excessively jovial, he brought a cup of white glass and broke it in their presence. Once again the broken vessel had the desired effect as the guests were disheartened. One commentator suggests that these accounts and the desire to dampen the festive atmosphere are the source for our custom to break a glass under the wedding canopy (Tosafot, 12th-14th centuries, France-Germany). A third tale is told, this one from the wedding feast of Mar the son of Ravina himself. The sages called Rav Hamnuna Zuti and requested: "Let the master sing for us." Perceiving the frivolous atmosphere, Rav Hamnuna Zuti opened: "Woe to us that we are destined to die! Woe to us that we are destined to die!" preferring a dirge over a wedding ditty (Rabbi Ya'acov Ibn Haviv, 15th-16th centuries, Spain-Portugal-Salonika). Recalling death, Rav Hamnuna Zuti succeeded not only in reducing the levity, but in changing the party atmosphere. With dampened spirits the sages sadly said: "How can we respond after what you have said?" Rav Hamnuna Zuti was not finished, citing a more frightening end than mere death: "Where is the Torah and where are the commandments that can protect us?" Dying with no spiritual achievements is even more depressing, suggested Rav Hamnuna Zuti. The Talmud, it appears, advocates tempering joyous occasions. Even at a wedding we are encouraged to keep our merriment in check, break a vessel to sadden this joyous occasion and talk about death at this celebration of life. Why are we so foreboding? Our unredeemed state is an inseparable part of our existence; do we really need to diminish happy occasions by recalling our woeful circumstances? Perhaps we should enjoy these flashes of joy, allowing ourselves to momentarily forget our doleful condition. While these dicta may seem to advocate a denial of pure pleasure, the concluding rule in this talmudic series puts a different spin on the joys of this world: Rabbi Yohanan recounts a tradition in the name of Rabbi Shimon bar Yohai: "It is forbidden to fill our mouths with laughter in this world." The source for this rule is the biblical promise that "then" laughter will fill our mouths and singing our tongues - that is, at a time when - they will say among the nations: "God has done great things with these people" (Psalms 126:2). Rabbi Yohanan's student-colleague, Reish Lakish, took this lesson to heart, and it was related about him that once he heard this teaching he never filled his mouth with laughter. The goal of curtailing enjoyment is not to limit our interaction with the delights of this world. The constraints suggested in this passage are designed to ensure that we continue to hope and strive for a better age. The ultimate goal may be to enjoy life, yet full pleasure is not possible in an unredeemed state. Sure we have moments of temporary delight, such as the creation of a new family at a wedding. Yet even at these occasions we are encouraged to curb our joy and spare a thought for the greater goal of a redeemed world where enjoyment will belong to all. The writer is on the faculty of Pardes Institute of Jewish Studies and is a rabbi in Tzur Hadassah.