Within the Christian faith, Holy Week is preceded by a time called Lent. It is a period of conversion, marked by prayer, fasting and almsgiving.
In Rome, the pope traditionally leads a penitential service in this time, to particularly call people to repentance. This service is marked by reflection and most importantly, confession.
After the readings and a homily by the pope, participants are able to receive the sacrament of reconciliation. Pope Francis is usually the first to go to the sacrament. Then, a select few are even able to go to confession to Pope Francis.
The ceremony begins at 5 p.m. local Rome time and will last around two hours. Three Friday's later, the Passion of Christ will be remembered in the same place in St. Peter's Basilica.