“Bellona, the Roman goddess of war, is presented by Rembrandt as a rather plain “girl next door,” probably to suggest that the new Dutch Republic was ready to repel foreign forces. Images of Mars and his sister Bellona occasionally decorated the headquarters of civic guard companies. The shield, with its frightful face of Medusa, was added at a late stage of work, probably in response to seeing a version of Rubens’s well-known painting of a severed Medusa’s head." (via)
"Rembrandt’s source for this painting, the Old Testament Book of Daniel, tells of a banquet Belshazzar, King of Babylon, gave for his nobles. At this banquet he blasphemously served wine in the sacred vessels his father Nebuchadnezzar had looted from the Temple in Jerusalem.
Rembrandt shows the moment when a divine hand appeared and wrote on the wall a phrase only Daniel could decipher. When transliterated the inscription reads: MENE, MENE, TEKEL, UPHARSIN. This is the interpretation: ‘God has numbered the days of your kingdom and brought it to an end; you have been weighed in the balances and found wanting; your kingdom is given to the Medes and Persians.’ That very night Belshazzar was slain.” (via)