The Martyrdom of St. Barbara
St. Barbara Chapel, Ljubljana Cathedral
As Barbara's father prepares to behead her, a putto arrives from Heaven with a laurel crown, emblematic of martyrdom. The fearful defensive gestures of the figures left and right anticipate the thunderbolt that will strike the father in the moment after he kills his daughter.
The tower in the background is the saint's attribute.
The cathedral was built in the early 18th century, and the frescoes in the Barbara chapel are from that same era, so this painting above the altar is probably not much later.
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More of St. Barbara
Photographed at the site by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.