what is meant by triduum and define it ?
Easter Triduum, Holy Triduum, or Paschal Triduum is the period of three days from Good Friday (seen as beginning with the service of the preceding evening) to the evening of Easter Sunday. It begins with the Thursday Mass of the Lord’s Supper and ends with evening prayer on Sunday. Since the 1955 reform by Pope Pius XII, the Easter Triduum, including as it does Easter Sunday, 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. so that the period that lasted from Thursday morning to before Easter Sunday began was once, in Anglo-Saxon times, referred to as “the still days”. In
