The Sacred Calendar I

Palm Sunday

The sacraments and other rituals of the church are rooted in an annual cycle of seasons and feasts with the celebration of Easter at its centre. In one sense, every Sunday is a celebration of the Resurrection of Christ. Nevertheless, Easter occupies a unique place in the Church's sacred calender. 

At the end of Lent is Holy week, a time set aside for the preparation of the Easter celebration. The core of Holy week is the Easter celebration. The core of Holy week is the Easter Triduum - Holy Thursday, Good Friday and Holy Saturday - and its climax, the Easter Vigil, when new member are initiated into the church, and then Easter Sunday itself.
The importance of Easter is reflected in the 50days that the season continues from Easter Sunday to Pentecost Sunday, when the church recalls the sending of the Holy Spirit and the commissioning of the apostles to preach and teach all nations. Imperial purple was the colour of prestige for the Roman ruling class.

Before Christ was crucified, soldiers draped him in a 'centurion's purple cloak', along with the crown of thorns to mock him; and so the colour purple came to be associated with the Passion of Christ.
Now during Lent, purple drapery is used to cover the sacred images in some churches, a practice designed to focus the attention of the faithful inward, away from external images. The dramtic removal of the drapery on Easter also reflects the removal of the darkness of death, which Christ as Redeemer brought to all.