In act three, scene one, Salarino asks Shylock what good it will be to receive a pound of Antonio's flesh, and Shylock responds by saying that he will use the merchant's flesh as fish bait. Shylock then admits that attaining Antonio's flesh will only feed his revenge and elaborates on the numerous times Antonio has publicly insulted and embarrassed him. Shylock continues to describe his deep-seated hatred towards Antonio and mentions that the merchant has also cost him a half a million ducats by loaning Christians money without interest. Shylock then questions Antonio's aimless animosity towards him and explains to Salarino that he is simply getting revenge because that is what he has been taught by the prejudiced Venetian Christians. Shylock says,
. . . The villainy you
teach me, I will execute, and it shall go hard but I
will better the instruction. (3.1.59–61)
Essentially, Shylock wants Antonio's flesh to satisfy his revenge and punish Antonio for the numerous times the merchant has wronged him.