Persecuted Christians were remembered during Thursday's Corpus Christi procession in Rome, where Pope Francis told the thousands taking part to walk and pray in unity with those who cannot express their faith so openly.

"Let us feel united with them: sing with them, give praise with them, worship with them," the Roman Pontiff said in his homily for Mass said in the Archbasilica of Saint John Lateran June 4, celebrated just before the procession.

"As we walk along the street, we feel in communion with the many brothers and sisters who are not free to express their faith in the Lord Jesus."

The Pope also remembered those who have been martyred for their faith.

"We venerate in our hearts those brothers and sisters who have been asked to sacrifice their lives in fidelity to Christ," he said.

"May their blood, united to that of the Lord, be a token of peace and reconciliation for the whole world."

During the procession for the feast of Corpus Christi, a monstrance containing the Blessed Sacrament was carried slowly through the streets on top a white truck, protected by two deacons and illuminated by candles.

The procession began after the evening Mass in Saint John Lateran, Rome's cathedral, and continued to the Basilica of Saint Mary Major. Thousands of people took part, including many of the prelates who concelebrated Mass with the Holy Father.

Pope Francis in his homily added that this procession can also be a way of "expressing our gratitude for the journey which God has made through the desert of our poverty, to free us from servitude, nourishing us with his love through the Sacrament of his Body and Blood."

The feast of Corpus Christi celebrates the real presence of Christ's Body and Blood in the Eucharist.

During the Mass, Pope Francis recalled how during the Last Supper, Christ gave his Body and Blood under the species of bread and wine.

"With this 'viaticum' over flowing with Grace, the disciples have everything they need for their long journey through history, extending God's reign to everyone," the Pope said.

"This Bread of Life has come down to us!" he said, adding that the never-ending awe which the Church has before of this reality fosters "contemplation, adoration, and memory."

Pope Francis reflected a few lines taken from the Office of Readings for the feast: "eat (Christ's Body), or you will have no part in him … drink (His Blood), lest you despair of your sinfulness."

By not obeying the Lord's Word, by not living together fraternally, by trying to be first, by not courageously giving witness to charity, by being unable to offer hope – in these ways, the Pope said, we separate ourselves from Christ.

The Eucharist, on the other hand, "is the bond of communion, the fulfillment of the Covenant, the living sign of Christ's love, who was humiliated and annihilated in order that we may remain united."

By taking part and nourishing ourselves with the Eucharist, "we are placed on a path which does not allow divisions," he continued.

Christ's presence among us under the appearance of bread and wine demands that "the power of love overcomes every wound," he said. "At the same time, it becomes communion with the poor, support for the weak, and fraternal awareness for those struggling to support the weight of daily life."

Pope Francis spoke of the "watering down" of our Christian dignity with "the idolatries of our time." He gave several examples of this contemporary "idolatry," including the viewing of oneself at the center of everything, arrogance, and not admitting fault.

"All of this degrades us, and makes us into mediocre, lukewarm, insipid, pagan Christians," he said.

The Roman Pontiff also spoke of how we are transformed by the grace which comes from the shedding of Christ's blood. "We always poor sinners, but the Blood of Christ frees us from our sins and restores our dignity," he said.

"Although undeserving, we are able to bring with sincere humility the love of our Lord and Savior to our brethren."