The heart of Jesus being pierced by a lance is only recorded in the Gospel according to St. John. But one of the soldiers pierced His side with a spear, and at once there came out blood and water. (19:34) St. John himself provides the reason why he is the only evangelist to record this event, He who saw it has borne witness--his testimony is true, and he knows that he tells the truth--that you also may believe. (19:35) Scholars have long accepted that this is St. John stating that he himself saw what he describes, as he is usually identified at the Beloved Disciple to whose care Christ entrusted His Blessed Mother just eight verses earlier.
The identity of the unnamed soldier in this verse has captured the Christian imagination for centuries. He is given the name Longinus in the apocryphal Acts of Pilate which is part of the so-called Gospel of Nicodemus (which also gives the names of the two thieves crucified with Our Lord as Dismas and Gestas). The Acts of Pilate may have originated earlier, but the complete Gospel of Nicodemus is no earlier than the fourth or fifth century.
The name Longinus is possibly derived the Latinized form of the Greek word lonche (λ?γχη), translated as lance in the aforementioned verse. Thus, it is possible that this name was merely given to the soldier based on his function in the Passion Narrative and that this was not actually his name. In the Dolorous Passion of Our Lord Jesus Christ, based on purported visions of Blessed Anne Catherine Emmerich, the name of soldier is given as Cassius. Media that use Emmerich’s Dolorous Passion as a source, most notably the film The Passion of the Christ and the historical novel The Spear, of which Longinus is the protagonist, use Cassius as the soldier’s name.
The verse in the Gospel according to St. John only refers to Longinus as a “soldier” with his rank not given. Due to the tradition that after the Crucifixion, Longinus converted, he is often conflated with the centurion in the Synoptic Passion narratives who states, “Truly, this was the Son of God” However, the Dolorous Passion gives the name of this centurion as Abenader. In The Passion, Cassius is a legionnaire, whereas in The Spear, Abenader is the primus pilus, the highest ranking centurion in the cohort, and Cassius Longinus is a junior ranking centurion under his command.
Longinus is an actual Roman name, but it is a cognomen, rather than a praenomen, which would be a personal name (such as Marcus or Lucius). Most Romans had only two nomina: the personal praenomen and the nomen of their gens or family (essentially the same as a modern surname). However, as the gens grew in size, a branch might adopt (or be given) a cognomen to distinguish it from the others. For example Julius Caesar, was of the Caesar branch of gens Iuli. His praenomen was Gaius. Interestingly, the full name of one of the leaders of the conspiracy to assassinate Caesar was Gaius Cassius Longinus.
In fact, Cassius Longinus was a relatively common Roman name. There are many consuls as well as various others political officials with the name Cassius Longinus. However, since consuls were usually senators this means they came from the patrician class. It would have been unlikely for a patrician to be serving as a common legionnaire, or even a centurion. In The Spear, Cassius refers to Caesar’s assassin as his “venerable great-uncle” but his status as an equestrian, rather than a patrician, is a key plot point in the novel. Moreover, while almost every gens had patrician branches as well as plebian ones, there was a Gaius Cassius Longinus who served as consul in A.D. 30, just three days before the likely historical date of Christ’s crucifixion. It seems highly unlikely that a family who held the consulship just three years prior would have a member serving as a centurion in the far flung, backwater province of Iudaea.
Tradition holds that after his conversion, St. Longinus gained the crown of martyrdom in Cappadocia, where had been living as a monk. According to the legend, Longinus was losing his sight when he thrust his spear into the side of the Crucified Christ but it was restored when the Precious Blood of Our Lord splashed on his eyes. When Longinus himself was executed via decapitation, his blood splashed on the governor who had ordered his execution, who likewise was cured of failing eyesight. Most interestingly, the feast of St. Longinus is March 15, the Ides of March made infamous by the assassination of Gaius Julius Caesar by, among others, Gaius Cassius Longinus.
Heart of Jesus, pierced by a lance, have mercy on us.
St. Longinus, pray for us!