The Sages of the Talmud offer three suggestions as to the significance of bringing joy to the bride and groom (Berakhot 6b). Each suggestion relates to a different aspect of a wedding, and their combination reflects the great joy involved: (a) Rejoicing with the bride and groom is like receiving the Torah; (b) it is like bringing a thanks offering; (c) it is like rebuilding one of the destroyed parts of Jerusalem. Each of these represents a way the wedding symbolizes God’s interaction with the world.

The joy at a wedding is a recognition of God’s command over everything:

The bride and groom are two separate entities, as this one is man and this one is woman, and as such they are completely separate. Their union is from God, may He be blessed, who brings them together…and when one brings joy to the groom, their union is completed, and [this expresses the notion that] it is God who unites the couple. This teaches that all changes in reality, like the fact that they separate into male and female, come from God. This aspect of [bringing joy to the bride and groom is] “as if one had offered a thanks offering” (Berakhot 6b)…which exists only to teach that all changes in reality are due to God.

The wedding is the establishment of a new entity by God and is like rebuilding one of the ruins of Jerusalem:

With regard to that which it says [that bringing joy to the bride and groom is considered] “as if one rebuilt one of Jerusalem’s ruins” (Berakhot 6b), the interpretation is that the union of the bride and groom brings about the completion of the formation of man; because he was previously considered a deficient form, and is now considered a complete form. This is considered like rebuilding the ruins of Jerusalem [the city of God], because this union of the bride and groom is an edifice built by God…

The completion of a person is comparable to the completion of the world:

It says that if he brings joy [to the bride and groom]: “He receives the reward of acquiring the Torah, which was given with five voices” (Berakhot 6b).… The Torah was given with five voices [the word “voice” appears five times in the account of the giving of the Torah (Exodus 19:16–19)]. [The Torah] is the divine order that was given to the world, and it brings completion to the world, as has been explained. Therefore, one who brings joy to the bride and groom is completing the union of the bride and groom, to the point where there is a completed reality, and a person is considered like the entire world…as was explained above that man is a microcosm of the entire world. Likewise, the Torah is a microcosm of the entire world. When one brings joy to the bride and groom, whose union is the completion of a person, who is the entire world, one thereby merits Torah, which is also the completed reality of the entire world, which is why the Torah was given with five voices, as has been explained. This interpretation is unquestionably true and clear to anyone who understands wisdom. (Maharal, Tiferet Yisrael 30)

Dancing before the bride causes her joy and delight, enabling her to reveal her inner desire, and her yearning for her husband. Each and every Jew, and the community of Israel as a whole, is the bride of God. In their spiritual essence they yearn for God, yet they must draw this desire and yearning out of their place of concealment to be revealed.

The heavenly bride is the community of Israel and the divine spark that is within each member of the Jewish people:

The matter of the heavenly bride is well known: It is the community of Israel as a whole [the source of all Jewish souls], and, in particular, it is in the divine spark within each and every Jew. The word bride [kalla] derives from kilayon, meaning completion or expiration as in: “My soul longs, indeed it expires [kalta], for the courtyards of the Lord” (Psalms 84:3). This refers to the natural, essential love that is rooted in every divine spark to be willing to die for the One, because it is indeed a part of the Divine and is drawn to its source…

The desire each person has to connect to God is concealed and needs to be revealed:

But even though one’s soul is rooted in the desire and passion to be constantly drawn to the source of its formation, as it says: “The spirit of the sons of man, does it ascend” (Ecclesiastes 3:21)…it is always moving upward…, nevertheless, this [desire] is hidden and enclosed in a person, and is in no way revealed…and this is why the word bride [kalla] derives from kilayon, as in: “My soul…expires [kalta],” as this refers to love that is concealed in the mysterious place in the heart of the Jewish people…

When we dance and rejoice it is possible to reveal that which is concealed:

This is the idea of dancing before the bride: Through dancing before her, we arouse within her a point of connection, bringing it from the concealed to the revealed, and she becomes a kind of receptacle in order to unite with her husband. For through her joy and delight, which we impart to her by dancing before her, she raises herself up, and that which is blocked inside her is aroused and becomes revealed, her desire for union… and so too with regard to the divine spark in the individual, which is called a bride; through the dance that we perform before it, that which was concealed within it [i.e., the soul’s love] is illuminated and revealed. (Rabbi Dovber Schneuri, Derushei Ĥatuna 2, p. 659)

The fine threads that are woven between the groom and the bride are strings that play the music of the Divine Presence at Mount Sinai. (Rabbi Shlomo Wolbe, Alei Shur 1)

Further reading: For more on love of God, see p. 107.