They didn't teach this in school
The cross was worshipped by the Pagan Celts long before the incarnation and death of Christ. "It is a fact," says Maurice, "not less remarkable than well-attested, that the Druids in their groves were accustomed to select the most stately and beautiful tree as an emblem of the Deity they adored, and having cut the side branches, they affixed two of the largest of them to the highest part of the trunk, in such a manner that those branches extended on each side like the arms of a man, and, together with the body, presented the appearance of a HUGE CROSS, and on the bark, in several places, was also inscribed the letter Thau." It was worshipped in Mexico for ages before the Roman Catholic missionaries set foot there, large stone crosses being erected, probably to the "god of rain." The cross thus widely worshipped, or regarded as a sacred emblem, was the unequivocal symbol of Bacchus, the Babylonian Messiah, for he was represented with a head-band covered with crosses..
http://www.biblebelievers.com/babylon/sect56.htm
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