Christian Cross. The Christian cross, seen as a representation of the instrument of the crucifixion of Jesus, is the best-known symbol of Christianity. It is related to the crucifix and to the more general family of cross symbols, the term cross itself being detached from the original specifically Christian meaning in modern English. The basic forms of the cross are the Latin cross with unequal arms and the Greek cross with equal arms, besides numerous variants, partly with confessional significance, such as the tau cross, the double-barred cross, triple-barred cross, cross-and-crosslets, and many heraldic variants, such as the cross potent, cross pattée, cross moline, cross fleury, etc. For a few centuries the emblem of Christ was a headless T-shaped Tau cross rather than a Latin cross. Elworthy considered this to originate from pagan druids who made Tau crosses of oak trees stripped of their branches, with two large limbs fastened at the top to represent a man's arm; this was Thau, or god. Further information: Instrument of Jesus' crucifixion, Early Christian descriptions of the execution cross, Crux simplex, and Tau cross John Pearson, Bishop of Chester 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. There are few extant examples of the cross in 2nd century Christian iconography. It has been argued that Christians were reluctant to use it as it depicts a purposely painful and gruesome method of public execution. 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. The extensive adoption of the cross as Christian iconographic symbol arose from the 4th century. 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 to mean the cross, when he repeated the idea, current as early as the apocryphal Epistle of Barnabas, that the number 318 in Genesis 14:14 was interpreted as a foreshadowing of the cross and of Jesus. His contemporary Tertullian rejected the accusation of Christians being adorers of the gibbet. 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. The oldest extant depiction of the execution of Jesus in any medium seems to be the second-century or early third-century relief on a jasper gemstone meant for use as an amulet, which is now in the British Museum in London. It portrays a naked bearded man whose arms are tied at the wrists by short strips to the transom of a T-shaped cross. An inscription in Greek on the obverse contains an invocation of the redeeming crucified Christ. On the reverse a later inscription by a different hand combines magical formulae with Christian terms. The catalogue of a 2007 exhibition says: The appearance of the Crucifixion on a gem of such an early date suggests that pictures of the subject may have been widespread even in the late second or early third century, most likely in conventional Christian contexts. The Jewish Encyclopedia says: The cross as a Christian symbol or seal came into use at least as early as the second century; and the marking of a cross upon the forehead and the chest was regarded as a talisman against the powers of demons.