PORTLAND — The Rev. Seamus P. Griesbach isn’t asking for much — just a few good men willing to give up having a family, autonomy and riches in order to dedicate their lives to spreading the Gospel in Maine.

It’s a decision he and 63 other active priests in the Roman Catholic Diocese of Portland have made. As of July 15, Griesbach will be the person responsible for helping men discern their callings to the priesthood in the state where fewer claim a religious affiliation than any other in the nation.

Last week, Bishop Robert Deeley appointed Griesbach, 35, to be director of vocations, effective July 15.

“Certainly, it will be a challenging assignment, and I am aware that the bishop has entrusted me with a critical responsibility in the diocese, which is in great need of priests in our day,” Griesbach said. “The work ahead promises to be a great adventure.”

Part of that challenge is the shortage of priests. In 2004, there were 100 active priests in the diocese. This year there are 64, according to Dave Guthro, communications director. Four men are attending seminaries and the diocese has several candidates in the midst of the discernment process.

Griesbach, 35, was ordained in 2007. He served as parochial vicar at St. Paul the Apostle Parish in Bangor from 2009 to 2013. For the past year, he has served as parochial vicar at St. Michael Parish in Augusta. His appointment to the new position was announced Monday.

He will replace the Rev. Nathan March, who was ordained with Griesbach. March’s new assignment has not yet been announced.

In announcing the assignment, Deeley describe Griesbach as “committed and driven.”

“Father Seamus is inspired by a great interest in assisting men who are discerning God’s call to serve as a priest,” he said Tuesday in an email. “He is looking forward to connecting with Catholics from all around Maine, helping them to see the many ways it is possible to follow Jesus and ultimately offering guidance to those who are called to serve the People of God on their pilgrimage to holiness as diocesan priests.”

Griesbach, whose new job will have him traveling throughout the state, is the youngest priest to hold the position since the Rev. Daniel P. Greenleaf, 38, did in 2000. Greenleaf will become the Diocesan Director of Seminarians on July 1. He will continue to serve as pastor of the Parish of the Holy Eucharist in northern Cumberland County.

Greenleaf was the director of vocations when Griesbach was going through the discernment process to decide if he would become a priest.

“Father Greenleaf was very involved in youth ministry and was very accessible when I was discerning,” Griesbach said Monday in an email. “We had great conversations and he helped me feel more comfortable with the idea and reality of the priesthood.

“He was able to bring men who were discerning together so that we could get to know each other, and he was willing to spend time with us,” he said. “His work really helped me to be open to the idea of the priesthood and eventually to have the courage to enter the seminary.”

Griesbach said he will live in the rectory at Our Lady of the Rosary Catholic Church in Sabattus, because it is “close to the interstate and St. Dominic’s.” The priest also said he is looking forward to working with Greenleaf.

The first step of any religious vocation promotion the diocese might initiate must include prayer and faith, according to Griesbach.

“The origin and development of an authentic religious vocation is a mysterious process that is aided in unseen yet powerful ways by prayer,” he said. “As Pope Francis often points out, a religious vocation is not merely a job but a supernatural, life-transforming call given by God for the good of the church and the world. When we see that the harvest is abundant but the laborers few, Jesus tells his disciples to pray to the master of the harvest to send out laborers. So we must pray hard today.

“A vocation to the priesthood or religious life is not created ex nihilo [out of nothing], it is a calling that is given to someone who already has responded to the gift of faith,” the priest continued. “So in the large sense, the most important thing for an increase in vocations is an increase in faith.”

That kind of faith of began to bubble up in Griesbach when he was five and his family began attending Mass again after a long absence. Home schooled in Lisbon Falls, he was an altar server at St. Cyril and Methodius Catholic Church, now named Holy Trinity Catholic Church. In his high school years, Griesbach joined the youth group at the Basilica of Saints Peter and Paul in Lewiston.

“I grew up with a lot of atheists, agnostics and Protestants,” he said Thursday in a telephone interview. “I felt that I couldn’t take my faith for granted. As a little kid, I had arguments with my atheist friends about what happened to people after they died. I ended up shouting, ‘I don’t care what you say, you won’t turn into compost when you die.’”

After completing his high school courses at home, Griesbach took a year off before attending St. Anselm College in Manchester, New Hampshire, and he spent six months at a monastery in Marvin, South Dakota, population 56.

“I lived with the monks in the cloister and worked around the grounds and did maintenance,” he said. “It was a very profound experience. I learned that being close to God, living a life of prayer was not an impoverishment at all.”

Griesbach said he thought about being a priest during college, “in-between girlfriends,” but did not begin a serious discernment process until he was teaching at what was then St. Dominic Regional High School in Auburn after he graduated from college.

“The pivotal moment was attending World Youth Day in 2002 in Toronto and seeing Pope John Paul II,” the priest said. “What he said about not being afraid really resonated with me.”

The Pope in his homily at the Mass on July 28, 2002, according the Vatican’s website, said, “And if, in the depths of your hearts, you feel the same call to the priesthood or consecrated life, do not be afraid to follow Christ on the royal road of the Cross!”

Griesbach said that after that, he simply wasn’t able to discern outside a seminary whether becoming a priest was what he was called to do. In 2003, he entered the Pontifical North American College in Rome. As a student, he was in St. Peter’s Square when the death of John Paul II was announced and when the election of Pope Benedict XVI was proclaimed.

As director of vocations, Griesbach said he must recognize that a calling to the priesthood is unique for every individual and, rarely is a straight path.

“I think it is very important that we teach young people and remind all Catholics that, from the very beginning of the Church, God has called certain men and women to leave behind everything and follow him in a radical kind of discipleship,” he said. “Christianity has been built up and sustained and renewed by the heroic efforts of thousands of men and women who gave up family, autonomy and riches in order to dedicate their lives exclusively to the service of God and neighbor. The best thing we can do is to help them not be afraid of that.”

Other priest assignments announced Monday included:

• The Rev. Daniel J. Baillargeon as pastor of Corpus Christi Parish in the Waterville area effective July 1. He has served as parochial vicar at St. Paul the Apostle in the Bangor area for the past year. Baillargeon was ordained in 2007.

• The Rev. Edward R. Clifford as parochial vicar for the Portland Peninsula and Island Parishes effective July 1. A native of Shawmut, Clifford was ordained June 14.

• The Rev. Joseph E. Daniels as pastor of St. Joseph Parish in Farmington and St. Rose of Lima Parish in Jay effective July 1. Ordained in 1990, he has served in Presque Isle, Lewiston, Bar Harbor, Bridgton and Fryeburg. Daniels is pastor of Corpus Christi Parish in Waterville.

• The Rev. Kyle L. Doustou as parochial vicar for the Parish of the Precious Blood in the Presque/Caribou area of Aroostook County. A native of Lewiston, Doustou was ordained May 30.

• The Rev. Emile H. Dube as temporary parochial vicar at All Saints Parish on the Boothbay Peninsula effective July 1. On Oct. 1, Dube will begin serving as parochial vicar at Stella Maris Parish in Hancock County. Dube was ordained in 2012, after 35 years as a brother in the Salesians of St. John Bosco in New York. He is currently parochial vicar at the Parish of the Precious Blood.

• The Rev. Brad Morin as parochial vicar at St. Paul the Apostle Parish in the Bangor area effective July 1. He was ordained June 6.

• The Rev. Paul Sullivan as parochial vicar at St. Michael Parish in the Augusta area effective July 15. Born in Fall River, Massachusetts, he attended the College of the Holy Cross in Worcester, Massachusetts, and studied at the New England Province of the Society of Jesus in Boston. He was ordained in 1983. He spent 12 years serving as pastor of St. Joseph Parish in Eastport and three years as pastor of St. Joseph Parish in Gardiner. Most recently, he served as retreat director of the Eastern Point Retreat House in Gloucester, Massachusetts.

In addition assignments, the diocese announced the Rev. Thomas Lequin, a Jesuit, will retire from active ministry effective July 1. A native of Holyoke, Massachusetts, he was ordained in 1977. During his 36 years of active ministry in Maine, Lequin served at parishes in Bangor, Brownville Junction, Westbrook, Presque Isle, Mars Hill, Indian Township, Woodland, Bingham, Farmington and Jay.