St. Peter ad Vincula

Saint Peter ad Vincula (Saint Peter in Chains) may refer to one of the following:

Celebrated on August 1, it was a liturgical feast (commemorating the Liberation of Saint Peter) in the pre-1962 General Calendar of the Roman Rite (see Tridentine Calendar, General Roman Calendar as in 1954 and General Roman Calendar of Pope Pius XII). A few traditionalist Catholics continue to celebrate "St Peter in Chains" as a major double feast day, but most of them follow the 1962 calendar. The Priestly Fraternity of St. Peter (FSSP), which otherwise follows the 1962 calendar, continues to observe this feast as a third class feast.

In the Orthodox Church, the feast of the "Veneration of the Precious Chains of the Holy and All-Glorious Apostle Peter" is celebrated on January 16.

The relic of the Chains of St. Peter were kept in Jerusalem, where they were venerated by Christian pilgrims. In the fourth century, the Patriarch of Jerusalem, St. Juvenal, presented them to Eudocia, wife of Emperor Theodosius the Younger, and she took them to Constantinople.

Later, Eudocia sent a portion of the chains to Rome with her daughter Licinia Eudoxia, the wife of Valentinian III. Licinia Eudoxia built the church of S. Petrus ad Vincula on the Esquiline Hill to house the relic. Also in Rome was the relic of the chains with which Peter was bound when he was imprisoned by Nero. These latter chains were placed in the same church as the chains from Jerusalem.

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Wikipedia