All depictions of Muhammad -- or so we hear daily -- are now and have always been forbidden in Islam. Art's history disputes this. True, that strict taboo today is honored now by almost all Muslims, but old paintings of the prophet -- finely brushed expensive ones, made carefully and piously by Muslims and for them -- are well known to most curators of Islamic art.

There are numerous examples in public institutions in Istanbul, Vienna, Edinburgh, London, Dublin, Los Angeles and New York.