On Sunday, Pope Francis led the crowds in St. Peter's Square in prayers for the victims of Thursday's attack in Nice which left more than 80 people dead, including ten children.

"The pain of the massacre is alive in our hearts," the Pope said during his post-Angelus address for July 17, during which he lamented the loss of "many innocent lives, even children," who were "mowed down" during the attack.  

The pontiff expressed his closeness to "every family, and to the entire French nation, which is in mourning."

"May God, the good Father, welcome all the victims in his peace, sustain the wounded, and comfort their families," he said.

Francis also prayed that "every plan for terror and death" might be dispersed to prevent anyone from spilling "his brother's blood."

In off-script remarks, he then extended "a fatherly and brotherly embrace to all the inhabitants of Nice, and all of the French nation."

Finally, the Pope invited the crowds to take part in a moment of prayerful silence, keeping in mind especially the victims and families of the massacre, before leading them in the recitation of the Hail Mary.  

84 people were killed and dozens were wounded on July 14 after a Tunisian man, Mohamed Lahouaiej-Bouhlel, intentionally drove a large truck through the crowded seafront Promenade des Anglais in the French city of Nice, the BBC reports.

The crowds had been celebrating Bastille Day, which marks the day of France's independence and is traditionally the country's biggest public holiday.

More in Vatican

Thursday's massacre is the third major terrorist attack to strike France in less than two years, and the second deadliest. On Nov. 13, 2015, nearly 130 people were killed in a series of attacks throughout Paris. In January of that same year, a total of 12 people were killed in the French capital after terrorists stormed the offices of the Charlie Hebdo satirical magazine.

Before leading the crowds in the Angelus prayer, Pope Francis offered his reflections on the day's Gospel account of Jesus being welcomed into the home of the two sisters, Martha and Mary.

In the account, Martha complains to Jesus that Mary has left her with all the busywork, to which he responds that Mary, who has been listening to him, has "chosen the better part."

In her "bustling" about to make sure Jesus was fed and cared for, Martha risked forgetting "the most important thing," the Pope said: "the presence of the guest, who in this instance was Jesus."

It is not enough for a guest to be "simply served, fed, and taken care of in every way," the pontiff said. "Above all, he needs to be listened to."

Since a guest is a person, with his own thoughts and feelings, it does not do for the hostess be so busy with serving that neither of them speak, he said. Rather, the guest should feel as though he is part of the family.

Jesus' response to Martha in this scene – that Mary had "chosen the better part" -- "finds its full meaning in reference to listening" to his word, Francis explained. This applies, for instance, to prayer.

(Story continues below)

"If we go to pray, for example, before the Crucifix, and we speak, speak, speak, and then leave, we don't listen to Jesus!" the pontiff said. "We do not allow him to speak to our hearts."

"Listen: this is the key word. Do not forget!"

Francis went on to reflect on hospitality as a "work of mercy," a "human and Christian virtue" which runs the risk of being neglected in today's world.

Whether it is among institutions which care for the sick and marginalized, or among families, it can happen that it is easier to provide services than it is to "listen and welcome," he said.

"We are always busy and have no time to listen," Francis said.

The Pope challenged those in the crowd to reflect on whether they take time to listen to their spouses, their children, their grandparents, the elderly, etc.

"I ask you to learn to listen, and to dedicate more time," the pontiff said. "In the ability to listen, there are the roots of peace."