PORTLAND — The Roman Catholic Diocese of Portland welcomed its 12th bishop Friday afternoon in a time-honored ceremony complete with religious pomp and circumstance.

The Installation Mass for new Bishop Robert Peter Deeley, 67, which took place at the ornate Cathedral for the Immaculate Conception, settled not only on Valentine’s Day but also in a convenient window between Thursday’s winter storm and another one predicted for Saturday.

In his remarks, Deeley gave the obligatory nods to the holiday and the weather, and in more pointed comments, suggested the diocese must recruit more priests and try to make amends with survivors of the Catholic Church’s sex abuse scandals.

He also hinted that the diocese would continue to be a vocal opponent of same-sex marriage and abortion under his watch.

More than 800 people were expected to turn out for the elaborate celebration, which was presided over by Cardinal Sean O’Malley of the Archdiocese of Boston, where Deeley served in various capacities during multiple stints totalling more than two decades of his career.

Deeley also spent eight years serving at the prestigious Congregation of the Doctrine of the Faith in Vatican City, often called the Holy Office.

Friday’s ceremony was a long time coming for Maine Catholics, who have been without a bishop since the previous Bishop Richard J. Malone was named the head of the Diocese of Buffalo, N.Y., 18 months ago.

Malone continued to serve as the apostolic administrator for Maine after the move to upstate New York, and was among three former Portland diocese bishops slated to be on hand for Deeley’s installation.

According to the most recent U.S. Census figures, the Roman Catholic Diocese of Portland continues to claim more members than any other denomination in the state, with more than 190,000. But that total still represents a significant dropoff from decades past — just 10 years earlier, more than 283,000 Mainers identified themselves as Catholics.

During his introductory news conference in December, Deeley said he hoped to channel the “joyful” approach of new Pope Francis locally in an attempt to re-energize Maine Catholics.

He reiterated that sentiment in his remarks delivered during Friday’s Installation Mass, and added that the diocese must “acknowledge that we need more priests” to refill the church’s ranks.

“It is our responsibility, priests and laity alike, to pray and to work for an increase in vocations to priesthood and religious life,” he said.

Deeley also made mention of the “grave failings of some of our number” in reference to cases of sexual abuse of children by priests, which he said “have been both a cause of shame and humiliation to the many.”

“We will always need to be attentive, in a particular way, to those whose lives have been so hurt by the scandals which have harmed them and the church,” said Deeley, who played a key role in the Congregation of the Doctrine of the Faith’s purging of thousands of priests credibly accused. “We will continue our efforts to support the survivors and all victims of abuse. And we will continue to work to see to it that the church is a safe environment for our children.”

In terms of political activism, Deeley touched on what will be the diocese’s continued advocacy against abortion and same-sex marriage, saying: “As we serve others, even though we can experience it as a real challenge in our world today, we must continue to bear witness to the dignity of human life and every person from conception to natural death, the dignity of Christian marriage and the good of children, which is intimately part of this sacred union.”

After the customary procession of Catholic leaders and representatives of ecumenical groups to start the event Friday, Fr. Louis J. Phillips, rector of Portland’s Cathedral of the Immaculate Conception, presented Deeley with a crucifix and ceremonial aspergillum for sprinkling holy water.

Archbishop Carlo Maria Vigano — who, as Apostolic Nuncio to the United States of America, serves as Pope Francis’ representative in this country — read the official Vatican letter declaring Deeley the 12th bishop of the Portland diocese.

Following several readings, O’Malley presented Deeley with the historic pastoral staff used since the diocese’s first bishop in 1855 and led him to the cathedra, the bishop’s throne, to receive congratulations from a line of diocesan representatives.

After the nearly two-and-a-half-hour ceremony, Catholics leaving the cathedral described the event as inspiring.

“It was a blessed ceremony to have our shepherd back,” said Ken Woodbury, who made the trek from Greenville to take in the celebration. “It was well worth the trip. Despite the weather, it was a beautiful ceremony.”

Mercy Hospital CEO Eileen Skinner echoed the “beautiful” adjective when stopped by a reporter exiting the cathedral.

“After not having a bishop for a year, this was amazing,” she said. “Coupled with Pope Francis and the new vision, it’s really energizing.”

Advocates for victims of the church sex abuse scandal reiterated their condemnation for the Catholic institution through the release of prepared statements before the Installation Mass.

“Let us not engage in such blind deference to the newly installed Catholic bishop, that we allow ourselves to forget for even one moment that in secular terms, Bishop Richard Deeley is the senior territorial executive of a worldwide organization whose leaders and employees have committed and covered up more felony sex crimes against children than any institution in the history of the world,” said Paul Kendrick of the Ignatius Group.