Animals
There is a significant amount of animal imagery used throughout the play, most frequently in a pejorative way as other characters compare Shylock to unsavory and subhuman forms. Animals like wolves, dogs, and vermin appear throughout the play to emphasize the disdain that the Christian characters hold toward Shylock for his miserly attitude and his Jewishness, which they perceive as inseparable.
Money
Of course, a recurring image in The Merchant of Venice is money, wealth, and things of value. The imagery of the three caskets – made of gold, silver, and lead – emphasizes the play's interrogation of appearances and the notion that not everything that looks grand is valuable.
Music
Music is considered a transformative and "sweet" motif in the play, and as such it is juxtaposed with Shylock's severe and controlling attitude. At the beginning of the play, Shylock demands that Jessica shut the windows so he does not have to hear the music coming in from the outside. Later, Lorenzo equates this type of behavior with that of schemers, traitors, and other unsavory characters.
Devils
Along with animals, Shylock is also frequently compared to a devil or demon throughout the play. Antonio warns Bassanio of Shylock's ability to seem "holy" when he is, in reality, the devil in disguise. The imagery of devils and other hellish creatures underscores the overarching Christian messages in the play as a whole. It also foreshadows Shylock's eventual forced conversion from Judaism to Christianity.
