If a person normally attends a Shiur (Torah class) on a certain night of the week, and one week he has a wedding to attend that night, which takes precedence?
The Vilna Gaon (Rav Eliyahu of Vilna, 1720-1797) noted that the Book of Mishleh speaks of an "Et Rekod" – "a time for dancing" – using the word "Rekod" instead of "Li’rkod." The missing "Lamed" in this word, the Gaon explained, alludes to the fact that when it is time to dance at a wedding, this Misva overrides "Lamed" – learning. The Misva of "Mesame’ah Hatan Ve’kala" – celebrating with the bride and groom – is so important that it even overrides Torah study. Therefore, participating in wedding festivities takes precedence over learning Torah.
However, this applies only to the "Rekod" – the dancing, as opposed to the ceremony. At the Hupa ceremony, the Hatan and Kala fulfill a Misva, but the people in attendance do not actively participate in a Misva. While it is certainly meaningful, and the guests answer "Amen" to several Berachot, this does not override Torah learning. Therefore, a person who has a scheduled learning session or Shiur at night should not miss his learning to attend the Hupa, but should miss learning for the dancing, in order to fulfill the Misva of celebrating with a bride and groom. It should also be noted that often the ceremony is delayed and begins well after its scheduled time, and thus one who attends a Hupa may end up spending the majority of his evening at the affair. Therefore, when possible, one should try to attend his regular Shiur and then go to the reception for the dancing and celebration.
An important exception to this rule is when attendance at the Hupa fulfills a Misva. If the Hatan and Kala, for whatever reason, do not have many people attending their wedding, and certainly if they might not have a Minyan at the ceremony, it is, without question, a Misva to attend the Hupa to bring the couple joy. And therefore under such circumstances, the Misva of attending the ceremony would override the Misva of Torah learning.
(Based on Rav Rahamim Moshe Shayo’s "Mehkereh Eretz," p. 295)
Summary: If a person has a conflict between his regular Torah class and a wedding, the Misva of dancing with the bride and groom takes precedence, and thus he should attend the reception at the expense of his Torah class. He should not, however, miss his Torah class to attend the Hupa, unless the couple will not be having many guests at the Hupa, in which case it is a Misva to attend the Hupa even at the expense of Torah learning.
