The Paschal Triduum or Easter Triduum, Holy Triduum, or the Three Days, is the period of three days that begins with the liturgy on the evening of Maundy Thursday, reaches its high point in the Easter Vigil, and closes with evening prayer on Easter Sunday. It is a moveable observance recalling the Passion, Crucifixion, Death, burial, and Resurrection of Jesus, as portrayed in the canonical Gospels.

Maundy Thursday or Holy Thursday, among other names, is the day during Holy Week that commemorates the Washing of the Feet (Maundy) and Last Supper of Jesus Christ with the Apostles, as described in the canonical gospels.