LOS ANGELES - The nation's Roman Catholic bishops have approved a new English translation for Mass that would change key prayers spoken for decades by millions of American parishioners.

Before Mass changes at the parish level, the American version must go to offices in the Holy See for final approval, a process that a key bishop said could take years.

The U.S. Conference of Catholic Bishops voted 173-29 at its biannual meeting Thursday for a new translation after a debate over several small changes in wording. Bishops had long been divided over the English version, both because of the timing of the change and the phrasing of some passages, but in the end the translation got more than the 168 votes it needed to move forward.

The vote on the Order of the Mass was aimed at satisfying Vatican calls for a translation that's closer to the Latin version.

Bishop Donald Trautman, chairman of the conference's Committee on Liturgy, said the vote marked the biggest changes since the Second Vatican Council, when the Latin Mass was replaced by the vernacular languages in each country.

"It's a new liturgical moment," Trautman said. "It is the first major item to call for change to the Mass text and it will affect the worship life of every Catholic in the United States and beyond."

The new translation alters the wording of key texts spoken by Catholics during worship, including the Nicene Creed, the Gloria, the Penitential Rite, the Sanctus and Communion.

Some have worried about changing a fundamental rite of worship that is so much a part of Catholic identity, especially now.

Mass attendance has been declining, the priest shortage has left a growing number of churches without a resident cleric, bishops and parishioners have been battling over the closure of old churches and schools, and the prelates have been trying to rebuild trust in their leadership after the clergy sex abuse crisis.

Before the meeting, the Rev. Thomas Reese, a senior fellow at the Woodstock Theological Center at Georgetown University and a Jesuit priest, said the new Mass would "cause chaos and real problems and the people who are going to be at the brunt end of it are the poor priests in the parishes."

Trautman acknowledged the adjustment could be difficult.

Minor changes to the wording of many portions of the Mass will be obvious to Catholics. The repeated exchanges "The Lord be with you" / "And also with you" between a priest and his congregation, for example, become "The Lord be with you" / "And with your spirit" in the updated version.

The prayer said before Communion would become "Lord, I am not worthy that you should enter under my roof," instead of "Lord, I am not worthy to receive you."

Survey results released by the conference's Committee on Liturgy last November found that U.S. bishops were split over whether the changes were necessary, but in the end the proposal won more than the 168 votes it needed for approval.

Some bishops said the changes would deepen lay people's understanding of Catholicism and Scripture. They said priests could use the changes to spark a discussion of the liturgical reasoning behind them, including citing biblical stories and the Latin version.

Bishops debated for about 20 minutes on a variety of wording changes, some pitting the familiar against the new. A proposal to change the words of the Nicene Creed from "one in being" to "consubstantial," which is closer to the Latin, failed.