President Obama will be the first U.S. President to attend a White House Seder.

The Obama family’s planned Seder at the White House on Thursday night apparently marks the first time a president has participated in the traditional Passover feast celebrating the exodus from Egypt, an administration official said.

It’s also a chance for the Obamas and several administration aides to look back on their own extraordinary journey over the last year.

A senior administration official explained that the Seder is a fulfillment of a vow that a small group of Obama campaign staff made during their Seder last year, on April 19.

Unable to go home for the holidays, the group of about 10 held an impromptu Seder in the basement of the Sheraton Hotel in Harrisburg, Pa., as the Obama campaign neared the end of its long primary campaign battle in the state. Then-Sen. Barack Obama participated in the Jewish ritual, along with a few friends who were traveling with him that day, a senior official said.

At the end of the ritual, after the traditional refrain “Next year in Jerusalem!” Sen. Obama and others in the group jokingly added, “Next year in the White House!”

So this year’s Seder “is meant not only to celebrate the holiday but also to reflect on all that has happened in our lives” since the Harrisburg Seder, the official said.