Crucifixion Diptych (van der Weyden) and theorized that the diptych represented two panels of a four-panel work – either the two-panelled left shutter of an altarpiece, or its center two panels. Based on pictorial style, Tucker argued that the large size of the human figures relative to the size of the panels was more in keeping with figures on the shutters of "carved" altarpieces than painted ones. He also noted that the shutters of carved altarpieces tend to de-emphasize the deep perspective commonly seen in painted altarpieces, which was consistent with the shallow pictorial space of the diptych. The diptych's figures are almost two-thirds life
St John Altarpiece (Memling) it presents a narrative, meant to emulate a vision the donors or viewers would experience when viewing the inside panels. Unlike most altarpieces of these types, Memling's fails to present a single unifying iconographical focus and is quite generalized with themes that seem unsuited for its specific location, according to Blum. She speculates the donors may have chosen the specific iconography, which "celebrated intercessory saints on the interior". It is an unusual painting in that it seems to "have served a double function: that of personal propitiation and that of public altarpiece, which portrayed the role of the religious community