A serious historical challenge comes from Dan Barker, former Christian evangelist turned atheist, in his book LOSING FAITH IN FAITH. In chapter 26, "Cross Examination", he argues that (much to his own surprise) there is no cross anywhere in the Bible. The word "cross" in the Bible is translated from the Greek word (insert Greek letters here, haha) pronounced stau-ross or stav-ross, and "crucify" is from stav-ro-oh. Lidell and Scott's A GREEK-ENGLISH LEXICON devine stav-ross as "an upright pale or stake. Of piles driven is to serve as a foundation. A pale for impaling a corpse." Thayer's Greek-English Lexicon, a "King James" reference much used by believers, agrees, and says the English word "staff" derives from stav-ross. W.E. Vine's EXPOSITORY DICTIONARY OF NEW TESTAMENT WORDS reports that stav-ross "denotes, primarily, an upright pale or stake. On such malefactors were nailed for execution. Both the noun and the verb... are originally to be distinguished from the ecclesiastical form of a two-beamed cross. The shape of the latter had its origin in ancient Chaldea and was used as the symbol of the god Tammuz (being in the shape of the mystic Tau, the initial of his name)... By the middle of the third century... pagans were received in the churches... and were permitted largely to retain their pagan signs and symbols. Hence the Tau, or T, in its most frequent forms, with the cross-piece lowered, was adopted to stand for the cross of Christ."
So, (he quotes other sources), the Romans used upright stakes for their executions, on which the victim was killed..., "it was sometimes pointed and thrust through the victim to pin him to the earth, or he was placed on top of the stake with its point upwards so that it gradually pierced his body; or he was tied upon it and left until death intervened; and there were other methods too. There is not a scrap of evidence that a stav-ross was ever in the form of a cross or even a T-shape."
There is no cross in early Christian art before the middle of the fifth century. The first clear crucifix appears in the seventh century. Before then Jesus is almost always depicted as a fish or a shepherd, never on a cross. Constantine's supposed fourth-century vision of a cross in the sky was not of the instrument of execution, it was of the Greek letter X (chi) with a P (rho) through it, the well known "monogram" of Christ, from the first two letters of the Greek word for Christ.
So, Dan Barker argues, the traditional "cross" is a symbol derived from pagan sources and is not a historically accurate shape of the Roman instrument of execution. He writes "scholars have been aware of the error but have been unable to resist the traditional mistranslation. In the Eighteenth century some Anglican bishops recommended eliminating the cross symbol altogether, but they were ignored."
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