What is it like to stand "shoulder-to-shoulder" with Pope Francis during the celebration of the Mass?

Fr. Michael Baggot told CNA that for him, "it was an opportunity to live this common priesthood, to share in the one priesthood of Christ with the Vicar of Christ and with so many of my brother priests from around the world."

Baggot, who will mark his first anniversary as a priest Dec. 16, first concelebrated at a papal Mass last year on Holy Thursday – it was the Chrism Mass in St. Peter's Basilica.

He told CNA it was "a very beautiful experience, especially since it came just a few months after my own priestly ordination."

"It was a very powerful experience of this priestly fraternity that perhaps I've read about and I've reflected on, and prayed about, but there it was a very tangible, visual, lived experience," he said, noting how he saw priests "from around the world who had come together for this event and to live this moment of prayer."

Baggot has also concelebrated at October's Mass of canonization for St. Oscar Romero, St. Pope Paul VI and five others, and at a Spanish-language Mass for the Feast of Our Lady of Guadalupe Dec. 12.

In 2017, before his priestly ordination, Baggot was also one of several deacons and altar servers who assisted at Pope Francis' Mass and Eucharistic procession outside the Archbasilica of St. John Lateran for the Feast of Corpus Christi.

During the Mass, he was called upon to incense Pope Francis and the crowds and to pass him the paten and chalice during the consecration, standing shoulder-to-shoulder with the pope as he elevated the Body and Blood of Christ. The whole experience, he said, was "powerful."

A priest with the Legionaries of Christ, Baggot has been in Rome studying and teaching since 2012. He is now a professor at the Pontifical Athenaeum Regina Apostolorum, and teaches for Christendom College's Rome program, of which he is an alumnus.

Baggot is also a convert from agnosticism, having joined the Catholic Church at the Easter Vigil Mass in 2003 as a senior in high school.

Priests who are concelebrating at a papal Mass inside St. Peter's Basilica begin by showing up about one and a half to two hours before the Mass. After a brief security check, they enter a large hallway inside the apostolic palace that is near a statue of Emperor Constantine.

Here the priests prepare for Mass, putting on their own albs, cinctures and stoles. The Vatican provides a chasuble – the outermost garment – for each of the priests.

"Which is pretty impressive when you think about it," remarked Baggot, because the number of chasubles the Vatican owns must be in the hundreds.

The priests are then given some brief instructions, which Baggot said have lately included the insistence that priests do not take any photos during the Mass – a request from Pope Francis himself.

He said that while he understands the desire to record the moment with a photo or video, he thinks it is more respectful of the Mass to keep cellphones put away.

"I think it's a very wise decision [of Pope Francis]," he noted, explaining that "it helps all of the priests, and I think all of the lay people as well, to live the Mass as a prayerful experience."

Shortly before the Eucharistic prayer, the concelebrating priests – usually around 100 – are called to approach the altar and are given gold ciboria holding the hosts to be consecrated.

The distribution of Holy Communion, Baggot explained, "is a tremendously powerful experience. Because I have never met or seen these pilgrims in my entire life, but I'm given this unique privilege of distributing the Body and Blood of Christ and giving them the most important gift I could possibly give."

He said it is also edifying "to see people from around the world who are gathered together in this common faith."

"While I had many beautiful experiences [at Mass] as a seminarian and as a religious in formation, even the experience of distributing communion… There's nothing quite like being a priest and saying these words of consecration and knowing that God is acting through you in a very particular way," he said.

According to Baggot, it is not difficult to concelebrate at a papal liturgy. A priest who would like to do so should just contact the Vatican's Prefecture of the Papal Household to ask for a special concelebrating ticket for priests.

To concelebrate at a papal Mass is "highly recommended," he said laughingly. "If you're a priest and have the opportunity, then by all means, take advantage of the opportunity. It's well worth arriving an hour and a half or two hours early to prepare."

"It's an incredibly beautiful experience. I can think of few better ways to live the universality of our Catholic Church."