Europeans in the 16th century started using X in place of Christ's name as shorthand for writing Christ. the Christian monks and scolars were knowledgeable of the the greek letter X,-Chi or khi- whicj is the first letter in the Greek word "Christos" or "Kristos" (Greek:CristoV) The Greek and Hebrew word "Christos" comes out "Messiah" and mean the same thing: "The anointed One." for many years the X was understood by Christian clergy and as time passed,many Christians, educated and not, were not aware of the meaning. Over time the meaning became lost and was later perceived as a sign of disrespect.