Sunday, April 1 through next Sunday, April 8, marks the Christian observance of Holy Week, which includes the eight days from Palm Sunday to the Sunday of Easter Day.

There are two really important times in the church year.

One is the 12 days of Christmas. This week is the other.

“The great joy of celebrating Holy Week is that we in the church are brought into a day-by-day experience of the last week of Jesus’ life,” SMU Canterbury Commons lay leader Paul Wheatley said. Holy Week is one of the most important events on the Christian calendar.

Holy Week forms a bridge between the 40-day season of fasting, penance and reflection known as Lent and the traditional 50-day celebration of the season of Easter, which culminates with Pentecost Sunday.

Observances of Holy Week vary within Christianity.

The Eastern Orthodox use a different liturgical calendar and will celebrate Easter Day on April 15 this year.

Some Protestant Christian denominations commemorate just Palm Sunday, Good Friday and Easter Day, while more liturgical denominations also mark Maundy Thursday and Holy Saturday.

Palm Sunday, which starts the eight days of Holy Week, marks the triumphal entry of Christ into Jerusalem.

Many congregations start their worship outdoors then process indoors, waving palms fronds while singing.

Maundy Thursday, Good Friday and Holy Saturday are often referred to as the Triduum, three days which, SMU associate chaplain and coordinator of religious life Judy Henneberger said, “call to us as church community, the significance in which the church community therefore and afterwards continues to gather.”

Henneberger said they give us the opportunity to enter into God’s time and get lost in the significance and understanding of who God is.

Maundy Thursday commemorates the Last Supper in which Christ and His disciples celebrated the Passover together for the last time during Christ’s earthly ministry.

Passover is the annual Jewish commemoration of deliverance from slavery in Egypt. Wine and unleavened bread play an important part in the Passover ritual as well as the Christian sacrament of Holy Communion which is based on the Last Supper.

Many congregations observe Maundy Thursday by having a special celebration of Holy Communion, that in addition to the sharing of bread and wine (or grape juice), includes the washing of feet.

In some places, the clergy wash the feet of all the members, while in others a member of the clergy will wash one person’s feet and that person will then wash the feet of the person behind them and so forth.

Some congregations also strip their altars of all decorations at the end of this liturgy.

Another practice by a number of congregations is to have an all night vigil of prayer on that evening.

Wheatley calls this “a different sort of all-nighter,” though in some places people take turns, signing up for one hour during the night.

Good Friday is a solemn day of prayer that commemorates Christ’s trial and execution by crucifixion.

Some congregations have special liturgies from noon to 3 p.m., which include readings and prayers connected to Good Friday.

The last day of the Triduum is Holy Saturday, a day of waiting.

The most, in terms of public worship, that might happen during the day at a church, would be a prayer gathering.

Since the liturgical calendar follows the ancient Jewish tradition of the next day beginning not at dawn or midnight but at sunset, some congregations celebrate the first worship of Easter Day, the Great Vigil of Easter, starting after the sun sets on Holy Saturday.

The Easter Vigil is a time when many congregations baptize adult converts.

Other congregations will start their celebration of Easter Day with a sunrise worship gathering.

Highland Park United Methodist is holding an outdoor “Sunrise Service” this year next to Prothro Hall, so the residents of Moore Hall should not be surprised if they wake up to singing and ringing bells on Sunday morning.

“Easter is a time of wonderful soul surprise,” Henneberger said. “On Easter, we are suddenly surprised because [Christ] is here in our midst, so once again we can be spiritually awakened, renewed, excited.”