The Mass -- the liturgical observance of the death and Resurrection of Christ -- is as familiar to Roman Catholics as it is central to their worship.
But some things are changing, and they will become increasingly apparent in the next several weeks as 4.2 million Catholics in the Los Angeles Archdiocese are asked to adjust to new ways of doing things.
Instead of crossing themselves with the sign of the cross before or after they receive Holy Communion -- which has been allowed but not required -- they now will be expected to slightly bow their head in reverence before receiving the sacraments. After they return to their pews, they will be asked to remain standing and join in congregational singing instead of kneeling in silent prayer. Prayer occurs only after everyone has received Communion.
For non-Catholics, the changes may seem like so much church talk. But to Catholics, the Mass culminates in the priest's Eucharistic prayer in which the church believes that the bread and wine become the body and blood of Jesus Christ. That belief explains in large part why Catholics are being asked now to bow their head in reverence just before receiving Communion. They are deemed to be in the presence of Christ.
There are other changes. During the time in the Mass when Catholics ritually exchange greetings with each other, known as the sign of peace, they will be asked to limit their exchanges -- a respectful handshake or embrace -- only to those who are nearby. Although it doesn't happen often, there will be no more wandering around the church seeking out friends to say "peace be with you."
The changes, contained in a new Vatican-approved "Instruction on the Roman Missal," are intended to instill more reverence during the Mass while visibly expressing the unity of those present through observing various forms in unison.
All Catholic dioceses across the United States are making the changes. Some small variations within the guidelines are allowed.
In the Los Angeles Archdiocese, which includes Los Angeles, Ventura and Santa Barbara counties, priests, deacons and lay leaders have been preparing to introduce the changes as the four-week season of Advent begins Nov. 30 in preparation for Christmas.
Last month, for example, more than 260 priests and deacons and more than 800 lay leaders participated in training sessions designed to help them educate rank-and-file Catholics. Orange County churches began implementing the changes in September.
For the most part, church officials said they expect few hitches. However, there have been a few early objections from some parishioners.
"Some handful said they would find a parish where they didn't have to do that. Most are cooperative and seem to be happy and content where the liturgy is going," said Father Michael C. Rocha, pastor of St. Mark Catholic Church in Venice. "Our community is pretty middle of the road."
Actually, the Los Angeles Archdiocese, the nation's largest, has in some instances been ahead of the curve. In 1997, for example, Cardinal Roger M. Mahony, the archbishop, issued a groundbreaking pastoral letter, "Gather Faithfully Together," which was a forerunner to some of the latest changes.
In his letter, Mahony urged Catholics in his archdiocese to lift their arms with upturned palms during the Lord's Prayer, known as the orans posture. He called for the use of bread instead of traditional Communion wafers. He also emphasized the importance of worshipers as an expression of "the body of Christ."
Though Mahony in no way diminished the church's belief that the consecrated bread and wine are in fact the body and blood of Jesus Christ, he came under fire at the time from Mother Angelica, founder of the Eternal Word Television Network.
She objected to what she claimed was the cardinal's ambiguity on "the real presence" in the sacraments. She called on Los Angeles Catholics to disobey the cardinal's letter. Mahony demanded, and got, an apology from her. Mahony made the changes in keeping with the decisions of the historic Second Vatican Council in the mid-1960s.
Generally, Catholics have adapted to those changes. But the new changes soon to take effect will take some education and getting used to, particularly the suggestion that Catholics remain standing immediately after Communion.
"Some people kneel because that's the prayer posture they've had all their lives," said Tod Tamberg, a spokesman for the archdiocese. When people do stand as they are now asked to do, it may turn some heads.
"You kind of wonder what they're doing standing up," Tamberg laughed. But, he said, they're following the new rules.
Remaining standing in the pews after receiving Communion until everyone has received the sacrament is an expression of membership in and solidarity with the whole "assembly" of God, said Sandra Dooley, director of the archdiocesan Office for Worship