Daniel: In the story of Susanna and the Elders, the youthful Daniel intervenes when two old men falsely accuse Susanna. See Susanna (Book of Daniel) at Wikipedia. Here, Shylock seems to be making the comparison because the judge (Portia in disguise) looks so young. Later, Gratiano will make the same comparison, but apparently because Daniel (as Portia does to Shylock) turns the tables on the accusers.
Susanna and the Elders by Guido Reni, (1575 - 1642) who was an Italian painter of high-Baroque style.
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