Although a popular argument for using contemporary music is Luther's use of "bar tunes," the actual historical precedent may not be as solid as some think. The best quote I've found on this is from Charles P. St-Onge in a paper he wrote at Concordia Seminary:
"But the controversy surrounding Luther’s use of both ‘religious’ and ‘secular’ folk music may well be beside the point. As observed earlier, the line in Medieval Germany between the sacred and the secular is, musically speaking, difficult to draw. A tune used to accompany a story about St. Anne may, the next night, be used to tell the news of the Emperor’s death, and then to describe the value of a good mistress. One historian of the period writes, “All types of [folk] music were monophonic…composed of four to eight lines of poetry, and based on simple musical structures such as the German Bar form (AAB).” Here is where the popular notion of Luther use of 'bar music' comes in. Luther did indeed use popular ‘bar’ music. What this means, however, is that Luther used a very common compositional technique in setting his hymns to music. It does not mean that Luther necessarily raided the taverns of Wittenberg for ‘secular’ tunes for his church. Rather, Luther wrote his hymns following an A-A-B ‘bar’ form. Such a form consists of a melodic system that repeats twice, followed by a unique and unrepeated melodic system."
stonge.intheway.org/documents/Music%20Wo...p%20and%20Luther.pdf
We must think more clearly about music as music (apart from the lyrics). An earlier response suggested that the use of a particular style of music could be considered "worldly" and that we must be "completely different" than the world. This commenter also suggested that Jesus was "different in every way," however this betrays a misunderstanding of how Jesus, in fact, acted the part of a Rabbi -- he had disciples, taught them in the accepted forums, and in well-know forms of teaching. His message was beyond what they had heard previously, but His methods were strikingly familiar to His listeners.
I would prefer that we think through the issue of music (as an art form) from a Biblical Worldview. Suggesting that a style becomes "Christian" just because the words have a Christian meaning is not enough. There is more to it, and this is something we must ponder and consider.
Mark Sooy