In the persecutions under Valerian in 258, numerous priests and bishops were put to death, while Christians belonging to the nobility or the Roman Senate were deprived of their goods and exiled. Pope St Sixtus II was one of the first victims of this persecution, being beheaded on August 6. A legend cited by St Ambrose of Milan says that Lawrence met the Pope on his way to his execution, where he is reported to have said, "Where are you going, my dear father, without your son? Where are you hurrying off to, holy priest, without your deacon? Before you never mounted the altar of sacrifice without your servant, and now you wish to do it without me?" The Pope is reported to have prophesied that "after three days you will follow me".
Lawrence is said to have been martyred on a gridiron. During his torture Lawrence cried out "This side’s done, turn me over and have a bite." ["Assum est, inquit, versa et manduca."]
Cyprian, the contemporary bishop of Carthage mentions the directive of Valerian that Christian bishops, presbyters, and deacons should forthwith be punished, and records the martyrdom of Xystus bishop of Rome, in accordance with it on August 6 (Wace).
According to lore, among the treasure of the Roman church entrusted to Lawrence for safe-keeping was the Holy Chalice, the cup from which Jesus and the Apostles drank at the Last Supper. Lawrence was able to spirit this away to Huesca with a letter and a supposed inventory, where it lay hidden and unregarded for centuries. When Augustine connects Lawrence with a chalice, it is the chalice of the Mass:
According to Christian mythology, the Holy Grail is a relic that was sent by St. Lawrence to his parents in Spain. He entrusted this sacred chalice to a friend whom he knew would travel back to Spain, his home country. While the Holy Chalice's exact journey through the centuries is disputed, it is generally accepted by Catholics that the Chalice was sent by his family to a monastery for preservation and veneration. Historical records indicate that this chalice has been venerated and preserved by a number of monks and monasteries through the ages. Today the Holy Grail is venerated in a special chapel in the Catholic Cathedral of Valencia, Spain, in the region of St Lawrence's birth and early life.
By tradition, Lawrence was sentenced at San Lorenzo in Miranda, martyred at San Lorenzo in Panisperna, and buried in the Via Tiburtina in the Catacomb of Cyriaca by Hippolytus and Justinus, a presbyter. Tradition holds that Lawrence was burned or "grilled" to death, hence his association with the gridiron. One of the early sources for the martyrdom of Saint Lawrence was the description by Aurelius Prudentius Clemens in his Peristephanon, Hymn II.
Constantine I is said to have built a small oratory in honour of the martyr, which was a station on the itineraries of the graves of the Roman martyrs by the 7th century. Pope Damasus I rebuilt or repaired the church, now known as San Lorenzo fuori le Mura, while the minor basilica of San Lorenzo in Panisperna was built over the place of his martyrdom. The gridiron of the martyrdom was placed by Pope Paschal II in the church of San Lorenzo in Lucina.
St Lawrence is one of the most widely venerated saints of the Roman Catholic Church. Lawrence is also venerated in the Anglo-Catholic tradition; a major church in the City of Sydney, Australia, situated in the civil (land division) parish of St Lawrence adopted St Lawrence as patron notwithstanding its primary dedication as 'Christ Church', and there was an Anglican order in Melbourne Victoria Australia, the order does not exist as such anymore but they founded the organisation known as the Brotherhood of St Laurence that still bears this name. Devotion to him was widespread by the 4th century. As his martyrdom occurred very early in Church history, many other Christians honor him as well.
St Lawrence is especially honored in the city of Rome, where he is one of the city's patrons. There are several churches in Rome dedicated to him, including San Lorenzo in Panisperma, traditionally identified as the place of his execution. He is invoked by librarians, cooks, and tanners as their patron. His celebration on 10 August has the rank of feast throughout the entire Catholic world. On this day, the reliquary containing his burnt head is displayed in the Vatican for veneration.
The Escorial Palace, situated at the foot of Mt. Abantos in the Sierra de Guadarrama, was built by King Philip II of Spain to commemorate the victory of Spanish forces over those of King Henry II of France at the Battle of St Quentin, which took place on the feast of St Lawrence on 10 August 1557. To honor the martyr, the entire floor plan of this imposing edifice was laid out in the form of a gridiron, the means by which St Lawrence was martyred.
"Father, you called Saint Lawrence to serve you by love and crowned his life with glorious martyrdom. Help us to be like him in loving you and doing your work. Grant this through our Lord Jesus Christ, your Son, who lives and reigns with you and the Holy Spirit, one God, for ever and ever. Amen.