Friedrich Schinkel identified it as the work of Hugo van der Goes. It was not until later that this theory became generally accepted. The central panel of the Portinari Triptych depicts the central Christian myths concerning the birth of the Christian saviour god: the nativity of Jesus, the adoration of the shepherds and the annunciation to the shepherds (in the far right background). Many interpretations of the iconography of the altarpiece have been proposed. The composition emphasizes the devotion to the Eucharist and the passion of Christ. The Eucharist is represented through the angels wearing liturgical vestments and the visual analogy of the sheaf of wheat with the body of Christ. The Passion is represented in the somber expressions of the figures and in the prominently placed flower still life in the foreground, which includes flowers such as a scarlet lily, white and purple irises and carnations. One of the containers in which the flowers are placed is of the albarello type. Albarelli were used as medicinal jars designed to hold apothecaries' ointments and dry drugs and thus reference in the picture the hospital setting (i.e. the hospital of Santa Maria Nuova) in which the altarpiece was to be displayed. Some of the flowers in the flower still life were in the Renaissance also used for medicinal purposes and thus also reference the hospital setting. These references to medicinal powers also allude to the miraculous birth of Jesus, which, according to Christian literature, happened without the usual birth pains. The birth of Jesus itself is also supposed to have healing powers by delivering mankind from the so-called original sin, the Christian doctrine of humanity's state of sin, which resulted from the fall of man. The side panels depict the male (left wing) and female (right wing) members of the Portinari donor family who commissioned and donated the altarpiece. The right wing also includes a scene of the annunciation to the Magi and the left wing a scene of the journey of Mary and Joseph to Bethlehem. Portraits Hugo van der Goes is regarded as one of the most significant portrait artists of 15th-century Europe. At that time portraiture was gaining importance in art because of the renewed importance attached to the individual fostered by the rise of humanism. No independent portraits by Hugo van der Goes have survived. His achievements in this genre are only known by the donor portraits