such an exquisite manner, that "Neither the mystical union that results in his work, nor his reality itself for that matter, seems capable of being rationally analyzed, explained or reconstructed." His treatment of architectural details, niches, colour and space is presented in such an inexplicable manner that "the particular objects or people we see before us have suddenly, jarringly, become symbols with religious truth". Paintings and other precious objects served an important aid in the religious life of those who could afford them. Prayer and meditative contemplation were means to attain salvation, while the very wealthy could also build churches (or extend existing ones), or commission artworks or other devotional pieces as a means to guarantee salvation in the afterlife. Vast numbers of Virgin and Child paintings were produced, and original designs were widely copied and exported. Many of the paintings were based on Byzantine prototypes of the 12th and 13th centuries, of which the Cambrai Madonna is probably the best known. In this way the traditions of the earlier centuries were absorbed and re-developed as a distinctly rich and complex iconographical tradition. Marian devotion grew from the 13th century, mostly forming around the concepts of the Immaculate Conception and her Assumption into heaven. In a culture that venerated the possession of relics as a means to bring the earthly closer to the divine, Mary left no bodily relics, thus assuming a special position between heaven and humanity. By the early 15th century, Mary had grown in importance within the Christian doctrine to the extent that she was commonly seen as the most accessible intercessor with God. It was thought that the length each person would need to suffer in limbo was proportional to their display of devotion while on earth. The veneration of Mary reached a peak in the early 15th century, an era that saw an unending demand for works depicting her likeness. From the mid-15th century, Netherlandish portrayals of the life of Christ tended to be centred on the iconography of the Man of Sorrows. Those who could afford to commissioned donor portraits. Such a commission was usually executed as part of a triptych, or later as a more affordable diptych. Van der Weyden popularised the existing northern tradition of half-length Marian portraits. These echoed the "miracle-working" Byzantine icons then popular in Italy. The format became extremely popular across the north, and his innovations are an important