Good Friday and Easter Saturday

Good Friday ('good' here meaning 'holy') was the longest day of Jesus' life, the day he died on the cross. Already around the year 300 did Christians follow in Jesus' footsteps up to Calvary where they venerated the cross.

Pietà, le Maître de Chaorce

Some years later a similar celebration is carried out in Rome. Then as now, all would receive the eucharist, which had been consecrated on the previous day. As part of the devout actions on Good Friday the believers will pray the Stations of the Cross. Good Friday is the most important day of of the year for penitence and fasting. 

Easter Saturday is the Day of Sorrow, where the Church and all the believers stand by the the grave of the Lord. No liturgy is celebrated, the altar is bare. This is the only day of the year when the eucharist is not received (except in times of mortal danger).