What is "Isru Chag?"

what is isru chag

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The term “Isru Chag” refers to the day after Pesach, Shavuot, and Sukkot. Although it is a regular workday, it is treated with some sanctity. The words “Isru Chag” can be found in the Book of Tehillim where it says "bind the festival offering (’Isru Chag’) to the corners of the altar,” making Isru Chag a “Wrapping up of the holiday.”

One does not fast on Isru Chag and the Tachanun prayers are not recited in the service. There are no work-related restrictions on Isru Chag. Since Isru Chag is the bridge between the recent holiday and the return to regular routine it is somewhat festive. For example, we are taught that that one who honors Isru Chag by indulging in good food and drink is considered to have built an altar and offered a sacrifice. Observing Isru Chag with some level of celebration also allows those in Eretz Yisrael to unite with those who live in the Diaspora who are celebrating Yom Tov Sheini on this day. In some communities, Isru Chag has a bit of a Chol Hamoed flavor. The Kabbalists teach that the holiness of the recent holiday can be felt on Isru Chag. Isru Chag also reminds us of the pilgrims who would return home with renewed excitement and inspiration after visiting Jerusalem for the holiday.

The days following Shavuot are especially festive. This is because those who were not able to bring the Shavuot offering to the Beit Hamikdash could do so any time during the six days that followed Shavuot. As such, tachanun is not recited during this entire period, (In Chuts la'arets some have the custom to start reciting Tachanun on the 13th of Sivan like in Erets Yisrael) Some Have the custom to start saying Tachanun the day after Isru-Chug.

Sukka 45b, Rema O.C. 429:2