splitting hairs

A Kashmiri Muslim woman prays on a cold winter morning during the festival of Eid-e-Milad at Hazratbal shrine in Srinagar January 25, 2013. Thousands of Kashmiri Muslims on Friday thronged to the shrine of Hazratbal, which houses a relic believed to be a hair from the beard of Prophet Mohammad, to celebrate Eid-e-Milad or the Prophet's birth anniversary.
REUTERS/Danish Ismail

If I get it correctly, Islam can be pretty testy about representations -- statuary, art, etc. -- of the Prophet. People have been murdered for such apostasy. But how do relics such as hairs differ?

There are probably enough fragments of the "true cross" around the world to heat the city of New York for a winter and Buddhist bones are not far behind, but neither Christianity nor Buddhism seems embarrassed or angered by such collections ... or anyway they don't issue fatwas.

Maybe it's just apples and oranges ... I don't know.