The Easter Vigil, after nightfall, is the first Mass of Easter. Holy Saturday (Latin: Sabbatum Sanctum) is the final day of Holy Week, between Good Friday and Easter Sunday, and when Christians prepare for the Christian feast of Easter. The day commemorates the Harrowing of Hell while Jesus Christ's body lay in the tomb. Christians of the Catholic, Lutheran, and Anglican denominations begin the celebration of the Easter Vigil service on Holy Saturday, which provides a transition to the season of Eastertide; in the Moravian Christian tradition, graves are decorated with flowers during the day of Holy Saturday and the celebration of the sunrise service starts before dawn on Easter Sunday. Congregations of the Reformed and Methodist denominations may hold either the Easter Vigil or an Easter Sunday sunrise service. Wiki link Dates computed from the General Roman Calendar. Text: Wikipedia (CC BY-SA).