Dressed in orange safety vests, green jumpsuits or other workers’ attire, Vatican gardeners, garbage collectors and cleaning crews joined Pope Francis for a 7 a.m. Mass March 22.

Usually in the Vatican, “we’re the invisible ones,” Luciano Cecchetti, coordinator of the Vatican gardeners and sanitation workers, told Vatican Radio after the Mass.

“To find ourselves before the Holy Father, at a Mass for us, is something that doesn’t happen every day. I turned and looked at the faces of the employees: We all left there misty-eyed,” he said.

After the Mass, there was time for private prayers. Pope Francis joined the others, going to a seat in the last row of chairs in the chapel of the Domus Sanctae Marthae, where he is staying.

Before the employees headed back to work, Pope Francis greeted each of one of them.

Almost all of the gardeners, Cecchetti said, offered to give the pope a guided visit of the Vatican Gardens.

“He didn’t say no,” he said.

Jesuit Father Federico Lombardi, Vatican spokesman, said the pope gave a brief homily, focused on the Gospel reading from St. John, in which some Jewish leaders pick up rocks, intending to stone Jesus for blasphemy.

The Vatican newspaper, L’Osservatore Romano, summarized the pope’s homily: “When we have hearts of stone, we pick up rocks and stone Jesus Christ in the form of our brothers and sisters, especially the weakest. We must open our hearts to love.”

Along with the outdoor crews, the congregation included members of three women’s religious orders who work in the Vatican: The Daughters of Charity of St. Vincent de Paul, who run a free pediatric clinic for the poor; the Daughters of the Sacred Hearts of Jesus and Mary, who care for retired nuncios living at the Vatican; and the Polish Presentation Sisters, who staff a Vatican storage facility.

Father Lombardi said the pope also had special guests at Mass March 21: the cooks, cleaning crew and other staff of the Domus Sanctae Marthae.