Palm Sunday is the Sunday before Easter marks the beginning of Holy Week, the holiest of weeks, in which the most important moments of Christ's life take place, which includes the suffering and torture He went through after His arrest, His journey while carrying the cross to Calvary where he was crucified and died, and finally, His rising from the dead. 

Palm Sunday is when Christ triumphantly entered from Galilee into Jerusalem to celebrate Passover with his disciples. According to the Gospels in the Bible, He entered Jerusalem on a young donkey (signifying humility) to shouts of 'Hosanna' from the townspeople, who threw clothes and palm leaves along his path and waved palm leaves as a sign of homage. The people happily welcomed him, because they believed that Christ would free them from the oppression of the Roman government at that time. Ironically, it was in Jerusalem that the Jews plotted against him and arrested him after Judas betrayed Him. On Palm Sunday, palm leaves are blessed and distributed to Christians, who then go in procession to the church waving the palm leaves.

As the blessed palm leaves cannot be discarded as trash. The Malankara (Indian) Orthodox Church keeps the palm leaves till Christmas when the leaves are burnt in a symbolic bonfire (Holy Campfire) during the liturgy. The bonfire symbolises the fire that the shepherds of Bethlehem made in the cave where Christ was born, while the burning of leaves symbolises the burning away of all impurities (evil/sin). The warmth of the fire symbolises salvation, which in the Christian belief, the crucifixion made possible for mankind.