Christians who were persecuted and who cannot openly express their faith were remembered during the Corpus Christi procession in Rome on Thursday, where Pope Francis asked thousands of attendees to pray in solidarity with them.

"Let us feel united with them: sing with them, give praise with them, worship with them," the oontiff said in his homily for Mass held at the Archbasilica of Saint John Lateran, as reported by the Catholic News Agency.

"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."

In his mass before the procession, the pope also held in reverence those who were 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."

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

Pope Francis also remembered how Christ gave his Body and Blood as represented by the bread and wine during the Last Supper.

"With this 'viaticum' overflowing with Grace, the disciples have everything they need for their long journey through history, extending God's reign to everyone," said the Catholic Church's top leader. "This Bread of Life has come down to us!"

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