SOUTH END -- At the conclusion of the Nov. 29 Cheverus Awards vespers service, Cardinal Seán P. O'Malley will seal a holy door in the Cathedral of the Holy Cross in preparation for the Extraordinary Jubilee Year of Mercy called for by Pope Francis.

The door will not be opened again until Dec. 13 during an 11:30 a.m. Mass, when it will be opened as a Holy Door of Mercy. It will remain open for one year.

The action is a way to celebrate the Jubilee Year of Mercy, which Pope Francis has decreed will begin on Dec. 8, the Feast of the Immaculate Conception. The jubilee year will focus on the theme of mercy.

Holy doors have been used since the 15th century as a ritual expression of conversion during jubilee years. Pilgrims and penitents pass through it as a gesture of leaving the past behind and crossing the threshold from sin to grace, from slavery to freedom, and from darkness to light.

"At times we are called to gaze even more attentively on mercy so that we may become a more effective sign of the Father's action in our lives. For this reason I have proclaimed an Extraordinary Jubilee of Mercy as a special time for the Church, a time when the witness of believers might grow stronger and more effectively," said Pope Francis, declaring the Holy Year at St. Peter's Basilica April 11.

In the words of Pope Francis, "There is only one way that opens wide the entrance into the life of communion with God: this is Jesus, the one and absolute way to salvation. To him alone can the words of the Psalmist be applied in full truth: 'This is the door of the Lord where the just may enter.'"

The Cheverus Awards vespers service, held at 3 p.m. Nov. 29, will see 127 laypersons, deacons, and religious honored with medals for their service to the Church. Most recipients are nominated by their pastors, and receive the award for performing their service in a humble, unrecognized way.