Today the altarpiece of the Virgin of Bethlehem is made up of a predella with an apostolate distributed along both sides of a tabernacle and a main body divided vertically into three sections of which the highest is the centre section crowned with an attic. This is also where the figure of the Virgin who gives her name to the altarpiece also stands. Each of the main subjects of the three vertical sections is framed by a series of smaller reliefs distributed over an archivolt. There is a total of twenty six such scenes.
The incorporation of these smaller reliefs represents a true innovation in the field of carved altarpieces and was undoubtedly inspired by pictorial works such as the Miraflores triptych by Van der Weyden that is currently in Berlin. Though this was more usually seen in altarpieces manufactured in Brussels from the last decade of the XV century, no other examples dating from the same period are known of. And, even if one was to appear, it is extremely doubtful that its decoration would occupy the entire trace of the arch.
As suggested by Bart Fransen, it seems doubtful that the apostolate belonged to the original altarpiece.
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