<P> John Pearson, Bishop of Chester (c. 1660) wrote in his commentary on the Apostles' Creed that the Greek word stauros originally signified "a straight standing Stake, Pale, or Palisador", but that, "when other transverse or prominent parts were added in a perfect Cross, it retained still the Original Name", and he declared: "The Form then of the Cross on which our Saviour suffered was not a simple, but a compounded, Figure, according to the Custom of the Romans, by whose Procurator he was condemned to die . In which there was not only a straight and erected piece of Wood fixed in the Earth, but also a transverse Beam fastned unto that towards the top thereof". </P> <P> During the first two centuries of Christianity, the cross was rare in Christian iconography, as it depicts a purposely painful and gruesome method of public execution and Christians were reluctant to use it . A symbol similar to the cross, the staurogram, was used to abbreviate the Greek word for cross in very early New Testament manuscripts such as P66, P45 and P75, almost like a nomen sacrum (nomina sacra). The extensive adoption of the cross as Christian iconographic symbol arose from the 4th century . </P> <P> The earliest depiction of the Christian Cross may be the Herculaneum Cross which was found in the city of Herculaneum, which was entombed in pyroclastic material along with Pompeii during the eruption of Mount Vesuvius in AD 79 . Another early depictions of the cross as a Christian symbol is the Alexamenos graffito . </P> <P> However, the cross symbol was already associated with Christians in the 2nd century, as is indicated in the anti-Christian arguments cited in the Octavius of Minucius Felix, chapters IX and XXIX, written at the end of that century or the beginning of the next, and by the fact that by the early 3rd century the cross had become so closely associated with Christ that Clement of Alexandria, who died between 211 and 216, could without fear of ambiguity use the phrase τὸ κυριακὸν σημεῖον (the Lord's sign) to mean the cross, when he repeated the idea, current as early as the apocryphal Epistle of Barnabas, that the number 318 (in Greek numerals, ΤΙΗ) in Genesis 14: 14 was interpreted as a foreshadowing (a "type") of the cross (T, an upright with crossbar, standing for 300) and of Jesus (ΙΗ, the first two letter of his name ΙΗΣΟΥΣ, standing for 18), and his contemporary Tertullian could designate the body of Christian believers as crucis religiosi, i.e. "devotees of the Cross". In his book De Corona, written in 204, Tertullian tells how it was already a tradition for Christians to trace repeatedly on their foreheads the sign of the cross . The crucifix, a cross upon which an image of Christ is present, is not known to have been used until the 6th century AD . </P>

When was the cross adopted as a symbol of christianity
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