In Act 1 of "The Merchant of Venice," what is the point of Shylock's story about Jacob and Laban? (Act 1, Scene 3, lines 67-93)? How does Shylock interpret the story? How does Antonio?
Antonio assumes that the story is simply about interest; Shylock, on the other hand, knows that it refers to what he calls "thrift" - we might rather call it "cheating".
The point is this: when Jacob decides to leave Laban's service and set up on his own, Laban asks what parting gift he'd like. Jacob asks for all the pied (black and white) lambs. Then, using rather improbable methods, Jacob manages to cheat it so that the number of pied lambs is hugely larger than it would normally have been, making his present much larger.
Antonio thinks this is a story simply about interest - not quite understanding, or not quite listening, clearly - but Shylock seems to intend it as a demonstration that anything goes in business.
There is one more point: and it works against Shylock. Later in the biblical tale, when Laban offers Jacob his eldest daughter to marry, rather than the one he actually has been courting, Rachel steals her father's images and elopes with Jacob. Perhaps if Shylock thought a few verses ahead in his Bible, he might see a foreshadowing of Jessica's elopement.
Shylock tells the story of Laban agreeing to allow Jacob all the spotted lambs in the flock. Knowing that a mother's lambs will look like whatever the mother looks at before she conceives, Jacob contrives to strip pieces of wood so that they are two-toned. He then puts them in front of the ewes. The ewes give birth to lots of spotted or multi-colored lambs, and Jacob profits.
To Shylock this is what interest is: simply acting shrewdly and using what you know to multiply your profits. Since this story comes from the Bible, Shylock implies it means we are all to act with similar foresight to maximize our wealth. Antonio disagrees, saying the abundance of spotted lambs had nothing to do with what Jacob did, but was simply an act of God. Shylock believes people have to be participants in their own wealth building; Antonio thinks wealth comes from God alone.