Palm Sunday is a Christian feast that marks the beginning of Holy Week and commemorates Jesus' triumphant return to the city of Jerusalem. In 2011, Palm Sunday will be celebrated on April 17.
Although the return to Jerusalem is recounted in all four canonical gospels, the traditions of Palm Sunday are largely based on the description from the Gospel of John.
They took palm branches and went out to meet him, shouting, "Hosanna!" "Blessed is he who comes in the name of the Lord!" (John 12:12-13)
By waving him with palm branches and using them to cover his path as he rode into the city on a donkey, the crowd indicated that he was revered and respected on the level of royalty.
To celebrate the occasion, many Christian churches -- both Catholic and Protestant as well as the Eastern churches -- distribute palm leaves to congregation members who then carry them in a procession either inside or outside of the church. Often the palm fronds are knotted or woven into small crosses that can be kept by individuals in their homes as a reminder of the lessons of Holy Week. In areas of the world where palm leaves are not readily available, other native plants may be substituted and Palm Sunday may be alternatively referred to as Yew Sunday, Willow Sunday, or whatever else is used in that locality.
The liturgy for Palm Sunday services usually follows the palm processions with a reading of the Passion story -- a meaningful reminder that many of the same crowd that welcomed Jesus to Jerusalem would participate in the mob that cheered for his death less than a week later.
For Christians, Palm Sunday marks the beginning of the final week of Lent and the events leading up to the crucifixion of Jesus on Good Friday and his resurrection on Easter. It is also connected to the following year's liturgical calendar as the palm leaves are often returned to the church to be burned in the next year's Ash Wednesday rituals.
Since Palm Sunday is a moveable feast that always falls on the Sunday prior to Easter the date varies by year.
Palm Sunday 2012 will fall on April 1.
Palm Sunday 2013 will be March 24.
Palm Sunday 2014 will be April 13.