what do you learn my the way Antonio deals with the bond with shylock?

Antonio and Shylock both step forward, and Portia asks Antonio if he confesses to signing the contract. He does, and Portia then says that Shylock therefore must be merciful. She delivers a short speech on mercy, but Shylock ignores it and demands the contract be fulfilled. Antonio represents the merits of Christianity and "Christian mercy" in the way he so freely signs the bond for Bassanio (with no interest of course) and then appeals for Christian mercy with Shylock.