Paschal Triduum

Easter Triduum, Holy Triduum, Paschal Triduum, or The Three Days, is the period of three days that begins with the liturgy on the evening of Maundy Thursday (Holy Thursday) and ends with evening prayer on Easter Sunday. As such, the Easter Triduum runs from the evening of Maundy Thursday (excluding most of Thursday) to the evening of Resurrection Sunday. It recalls the passion, death, burial, and resurrection of Jesus, as portrayed in the canonical Gospels.

In the Anglican, Lutheran, Methodist, and Reformed traditions, the Paschal Triduum straddles the two liturgical seasons of Lent and Easter in the Church calendar; however, in the Roman Catholic tradition, since the 1955 reform by Pope Pius XII, the Easter Triduum has been more clearly distinguished as a separate liturgical period. Previously, all these celebrations were advanced by more than twelve hours. The Mass of the Lord's Supper and the Easter Vigil were celebrated in the morning of Thursday and Saturday respectively, and Holy Week and Lent were seen as ending only on the approach of Easter Sunday.

After the Gloria in Excelsis Deo at the Mass of the Lord's Supper all church bells are silenced and the organ is not used. The period that lasted from Thursday morning to before Easter Sunday began was once, in Anglo-Saxon times, referred to as "the still days".

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