Earthly beauty is a reflection of that which is to be found in heaven. Verily, God is beautiful and loves that which is beautiful." This Hadith--a saying of Muhammad or one of his earliest followers--is quoted in the catalog to a remarkable exhibition showing in Amsterdam's Nieuwe Kerk called "Earthly Beauty, Heavenly Art." The exhibition, which transfers in slightly reduced form to St. Petersburg's Hermitage Museum in May, aims both to display the diversity of 1,200 years of Muslim creativity and to identify the main characteristics of Islam as expressed in the art it inspired.

"Traditionally, exhibitions like this of Islamic art are put up on a historical or regional basis," explains John Vrieze, chief curator of the exhibition. "But we sort of tossed everything together, because our basic aim is to show that there is a certain common characteristic of art that is Islamic." Vrieze and his colleagues have certainly tossed together a wonderful show, including loans from all the major collections of the world and particularly impressive contributions from the Hermitage and the private Khalili collection based in London. The works of art are arranged according to themes--mosque, pilgrimages, word, Koran, mysticism, palace, mausoleum, garden and paradise--regardless of when and where they were created. The viewer moves between sections, examining here a 16th century Iranian carpet or a 20th century Javanese batik, there a stunning array of 8th and 9th century Korans from Yemen or some glowing miniatures from the Mogul courts of 17th century India. The cumulative impression is of the many manifestations of Islam's rich culture.

What connecting thread can be discerned from this spectacular accumulation, other than the superlative aesthetic quality of virtually every object on display? The importance of beauty as an aspect of creation is repeatedly stressed in everything from precious objets d'art like Egyptian crystal or golden jewelry to domestic pottery, water jars or wall tiles: all these things, the everyday as much as the rare, are rendered in handsome style that reflects the transcendent beauty of Allah's creation. The distinction between art and craft is blurred, so a utilitarian object is made with as much care and love as a work of what Vrieze describes as "Art with a capital A." Many of the functional objects have a spiritual quality as well: a beautiful lamp suggests the light of Islam; the name of Allah appears as a decorative principle on bowls and vases; and a prayer rug represents a niche in which a plant grows, to suggest the garden of paradise that awaits the pious Muslim after death.

The importance of decoration and the development of a sophisticated form of abstract ornamentation are vital to the art of a religion which forbids the representation of any living creature with a soul--a prohibition originally intended to protect Muslims from idolatry. It also restrained artists from the damnable arrogance of aspiring to imitate Allah's creation of life. As a result, geometric designs are a popular component of Islamic art. Besides being abstract by nature, they also have a religious significance in their suggestion of the orderly harmony of the divine. Examples of abstract attempts to reflect the design behind creation are seen again and again in this exhibition, along with evidence of the renowned Muslim skill in mathematics and astronomy.

This impulse toward decoration can similarly be seen in the many copies of the Koran on display. Every Koran, being a direct transcript of the words of Allah to his prophet Muhammad, is not just a work of literature for Muslims but a sacred object in its own right. Therefore the text is often embellished with sophisticated calligraphy, an important branch of Islamic art which is well represented in the exhibition. Islamic calligraphers developed a variety of beautiful scripts: some chaste and monumental, like the Kufic used in stone inscriptions, others so elaborate that they become almost impossible to decipher. For Muslims, the word itself in the form of written script and calligraphy is of paramount spiritual importance, so words figure prominently in Islamic designs. For example, a large silk panel consists of the single word Allah, endlessly repeated in a trance-like blue haze. A similar impression of impersonal spirituality arises from 20th century Abstract Impressionists like Mark Rothko or Barnett Newman, but this panel was woven in the 18th century. The sheer prodigality of beauty in these religious objects reveals Islam as a religion that is far from being narrowly puritanical. The sensuous loveliness of Islamic art is well represented by the huge Alhambra vase, from Moorish Spain and loaned by the Hermitage, on which calligraphy is a major ingredient of the design. The Arabic word "pleasure" appears in a band of circles around the vase, and underneath it an echoing motif is created by the repeated word "health," as though the object is sanctioning both qualities as part of the religious life.

In privileged Muslim society the prohibition concerning the representation of living beings was often broken, no doubt because the members of the elegant Islamic courts felt that they were above the dictates of the religious law in force in less exalted circles. Wealthy rulers like the Moguls in India were also avid collectors of Western art, and their court artists were strongly influenced by Italian and Flemish models. A 17th century Indian depiction of the Last Judgment resembles Christian paintings on the same theme. This is a very rare example of the treatment of a religious subject with negative elements--there are countless references to paradise in Islamic art, few to hell. But even in this picture, hell looks a place of discomfort rather than torment, a sort of overcrowded sauna over which human souls must negotiate a precarious narrow bridge under the direction of a muscular blue demon. A nervous queue of pot-bellied rich men watch apprehensively as their virtuously skinny counterparts, touchingly vulnerable with their droopy moustaches and hairy chests, edge their way across the pit toward paradise. This vigorous and witty composition is filled with all manner of exotic specimens of humanity, including dog-faced people, men with heads but no bodies, and strange individuals who live with their feet in the air, all awaiting judgment under the calm gaze of the blessed souls already in paradise.

There are many other examples of representative art in court circles: an appealing painting of the much-loved infant son of Shah Jahan, who created the Taj Mahal as a mausoleum for his adored young wife Mumtaz, and a portrait of the elderly Shah Jahan himself, a nimbus of fire around his head (an adaptation of the Christian convention of the halo). The emperor stands within a wide border from which angelic figures look down as an expertly rendered lion and lamb calmly confront each other in anticipation of the Islamic paradise where all animals will live at peace with one another.

Islamic courts produced many such images in contravention of religious strictures, including one intriguing and mysterious page from a book of automata produced at the Egyptian court of Amir Nasruddin Muhammad in 1354. It shows a design for a model figure who, after his head was filled with wine, topped up a goblet held in his right hand from a bottle in his left. It is not known whether this whimsical object was ever constructed or remained someone's irreligious fancy.

Not everyone in the Islamic world was prepared to wink at the representation of living things, however. The exhibition includes examples of the Islamic tradition of iconoclasm--the destruction of images regarded as irreligious and damnable. A series of ceramic wall panels from 13th century Iran shows a quotation from the Koran in blue against an ornate background over which a vine wanders. Small birds perch in the vegetation, depicted as delicately as the twisting foliage of the vine; but someone has hacked off all their heads. And there is an extraordinary 13th century Iranian water jug, originally inlaid with silver, shaped like a cow being suckled by its calf with a lion on its back gnawing at its hump. A closer inspection of this richly suggestive piece, which Vrieze sees as emblematic of the unending cycle of birth, nourishment and death, reveals that the throats of the cow and the calf have been slit--either by an indignant iconoclast or by the craftsman Ali bin Muhammad ibn Abul-I-Qasim himself. It is as though he wished to reassure us that what we are seeing is not a representation of living beings at all, thus letting us enjoy the beauty of the object without running the risk of committing idol worship--and at the same time allowing him to avoid the wrath of Allah directed at those who usurp the divine prerogative by creating the forms of lifelike beings.

There was no problem in depicting vegetation, however, plants not being considered to have souls. From its earliest appearances Islamic art gives us a proliferation of plant designs, sometimes stylized to the point of abstraction, sometimes realistic, delicate, tossing in an imaginary paradisical breeze--heaven, in Islamic culture, is depicted as a garden, the Arabic word for paradise, djanna, being the same word for garden. Something of the ambience of an Islamic garden is created in this exhibition, which has trickling water, plants and caged singing birds as part of the display--a piquant effect in the baroque interior of Amsterdam's magnificent Nieuwe Kerk.

Many of these artifacts made their way to the West after crusaders looted wealthy Muslim homes and despoiled mosques, carrying off the wealth of their murdered victims to enrich the treasuries of European churches and cathedrals. Others were gifts to Western ambassadors posted to Islamic courts, who in turn donated works of European art--the rich collection of Islamic works in the Hermitage started as gifts from Shah Jahan to the Czarina Elizabeth, and many Islamic textiles were cut down and refashioned for use as liturgical vestments in the Russian Orthodox Church, some of which are on show--magnificently--in this exhibition. A lively cross-fertilization between the two cultures developed, of which one elegant and slightly disconcerting example is a crystal drinking horn, obviously commissioned by a Christian and fashioned in 14th century Syria, decorated with Arabic words and pictures of the saints. Later, in 16th century Germany, it was set in gold and further ornamented with religious figurines in a most un-Islamic manner.

"In a multicultural society," explains Vrieze, "it's really important that people know a little bit more about Islamic culture." In the Netherlands now, 4% of the population is Muslim and Islam is the second most practiced religion after Christianity. It is steadily gaining new adherents. The exhibition has prompted much interest among Dutch Muslims, for whom many of the objects on show are not simply things of beauty or of historical interest but also objects of great spiritual power and religious significance, such as the woven curtain of the Kaaba--the holiest shrine of Islam--at Mecca, one of the most venerated objects of Islam which is on display. As the catalog explains, it is the solemn duty of art to act as the earthly reflection of Allah's divine glory and bear witness to it. Muslims the world over share the belief expressed in the Koran: "To make a beautiful work is an act of devotion that sanctifies the maker; equally blessed is the person who gains enjoyment from the created object." And certainly there will be few people coming away from "Earthly Beauty, Heavenly Art" or its later incarnation in St. Petersburg who will not have felt their spirits lifted by it.