Most older Catholics may remember an afternoon devotional service which usually took place from noon to 3 p.m. It was called "Tre Ore" service ("tre ore" is Italian for "three hours"). This custom began in the 17th century.
Unlike a liturgy, the prayers, readings and rituals of a devotional service can be created and adapted by the local community. That's why Tre Ore services varied from parish to parish. Some parishes chose to give a meditation on what are called Christ's "Seven Last Words" on the cross. Others used a Tenebrae Service (the sorrowful lauds and matins of the Divine Office) for the last three days of Holy Week.
In 1955, Pope Pius XII moved the liturgy of Good Friday to the afternoon, and it has gradually replaced the Tre Ore devotional service.
Since Vatican II, Good Friday has been celebrated as part of the Sacred Triduum ("three holy days") with a special liturgy used on this day. The heart of this Good Friday liturgy is the proclamation of the passion from the Gospel of John, and the adoration of the cross.
- Little Black Book, Diocese of Saginaw