Shylock will indeed take the flesh. His statement, however, may not only perturb the two men on the Rialto, but would most likely terrify and offend any reader or audience member, too. But Shylock quickly gets himself out of the perhaps bad graces of his listeners and makes his reason, the use of the flesh (that which is not his own), a bit more reasonable, and understandable: “if it will feed nothing else, it will feed my revenge.”
Very astute that Shakespeare would have two of his most profound leads, Lear and Shylock, be of like mind and like ability to make quick and strong replies to questions that nag them so. Both men suffer from what can be considered a Job-complex, even though everything that they’ve lost (that they want back: daughters, kingdom, ducats) they’ve brought about themselves. But both want what they feel is due to them. Both want (and get, in different ways) their day in court. And when that happens, like Lear, whose revenges shall be the terrors of the earth, so too will Shylock’s execution of revenge “go hard” and “better the instruction.” Each man’s sense of entitlement is not meant for others to comprehend, but to accept, abide by, and accommodate.
Lear’s command to “reason not the need” is often read as meaning, “do not measure or calculate the need,” but can also be read and performed as meaning, “I do not need a reason,” and can be performed in a very measured way (even though the line is often taken as the precursor to the storm that begins, aptly, toward the end of this speech in 2.4 and to the great storm speech of 3.2). Likewise, there are different ways that Shylock’s “bait fish” line can be read and performed. Two interpretations, specifically, that come to mind are that of David Suchet and that of Patrick Stewart in the fourth episode of the Playing Shakespeare series led by John Barton in the early 80s (available on DVD). Both men played Shylock at different times under Barton’s direction, but in this program we get to see both men perform nearly every speech made by Shylock. As for this particular line, Suchet’s interpretation is driven by anger, and Stewart’s almost by madness or one could even say Joker-like hysterics. Both are very interesting and suitable enough for the part. Olivier seems to just pass over the line altogether, and not give it much emphasis. A possible third interpretation, one that also perhaps does not require as much effusiveness as it is given by Suchet and Stewart, is more matter of fact, as if to almost say, “What difference does it make?” which speaks to the sense of entitlement described earlier. Shylock does not immediately have to make heaven’s vault crack, as one might be inclined to have him or Lear do right off the bat, but rather maybe build up to the emphasis where it is most needed. Hamlet’s words, as ever, remain germane: an actor ought to acquire and beget a temperance that may give the whirlwind of passion smoothness.