First, the big elephant in the room; they need to find some reliable evidence that there ever was a historical Jesus . . .
http://www.rationalresponders.com/fo...dence_of_jesus
There have been a number of hoaxes in this area:
http://www.cnn.com/2003/TECH/science/06/18/jesus.box/
A stone box touted as the oldest archaeological evidence of Jesus is, in fact, a well-crafted fake, Israeli archaeological experts say.
The box, an object known as an ossuary, was said to have contained the bones of Jesus' brother James.
Shroud of Turin:
http://skepdic.com/shroud.html
all the evidence points toward the medieval forgery hypothesis
The Trier Cathedral in Germany is said to contain the
Holy Robe of Christ:
http://www.sacred-destinations.com/g...-cathedral.htm
The Empress St. Helena is known for her pilgrimages to the Holy Land, and pious legend has it that she brought back the Holy Robe of Christ from Jerusalem and entrusted it to her son's new church at Trier. The Holy Robe is the seamless garment said to be worn by Christ during the Crucifixion. It first makes an appearance in written documents in the 12th century; it was first displayed at the church in the 16th century for a period of 23 days, during which more than 100,000 pilgrims came to venerate it. It has been periodically displayed since then, attracting ever-larger crowds. The last exposition of the relic, for three weeks in 1933, drew 2 million pilgrims. In 1959, the relic was sealed in a splendid shrine in its own chapel, where it remains today.