The left panel depicts the Naming of John the Baptist.
Elisabeth lies in bed in the background after giving birth, while the pregnant Mary, the future mother of Jesus, brings the newborn child to his father Zacharias. Zacharias had been struck dumb for his doubts when an angel told him, during service in the temple, that he was to be the father of a son (this scene is shown in the lowest archivolt relief on the left). He therefore has to write down the name of the child. Mary, as the more important saint, is distinguished from Zacharias and Elisabeth by her aureole.
The side panels of the St John Altarpiece do not merely show the beginning and end of the Baptist's earthly life. The parallels between the pictorial motifs also express moral conflict. On the left, the chaste Virgin Mary holds the newborn baby in her arms; she and Zacharias are looking at one another gravely, aware of the significance of the event.
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