Good Friday commemorates the crucifixion and death of Jesus Christ. This is a pivotal event in Christian history, as it represents the suffering and ultimate sacrifice of Jesus' life. The crucifixion was the culmination of a number of events in Holy Week, including: the triumphal return of Jesus to Jerusalem on Palm Sunday; the washing of the disciples' feet by Jesus; and the Last Supper on Maundy Thursday.
The ritual texts on Good Friday name this liturgy as the "CELEBRATION" of the Lord's Passion. This is not a celebration as in a party or a joyous and rousing event. Rather, it is a continuing celebration of the death and resurrection of the Lord that is celebrated through Easter Sunday.
Christians don't celebrate this liturgy as if it's a funeral. Instead, they approach Good Friday with thankful hearts because they know that the death commemorated on this day ended in resurrection.
Easter Sunday is the most important day on the Christian calendar because it is a celebration of the Resurrection. Belief in the Resurrection is a critical defining point of Christianity. Many non-Christians may acknowledge the birth, existence and death of Jesus, but it is the Resurrection that is a purely Christian belief.
Believe it or not, some modern traditions that may appear to have a tenuous connection, actually have roots in the truest meaning of Easter. For example, the practice of hiding decorated eggs for children to find represents a coming out of the womb/tomb (i.e., Easter's intertwined themes of fertility and resurrection). Getting dressed up in new clothes also represents the new beginnings that are thematic of Easter.
This is a joyous day for Christians, reminding them of His love for us and his promise of eternal life and everlasting peace.
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