because Antonio would lend money without interest. he had also insulted him by calling him a dog and spat on his beard and robes.antonio didn't like the jews. he also hated as Antonio was a Christian

Shylock hates Antonio because Antonio has the privilege of being a wealthy Venetian who charges no interest on his loans, and he also hates Antonio for being a Christian. Additionally, Shylock hates Antonio for the outspoken disdain that Antonio displays towards him.Antonio not only loans money interest-free to many, he has also covered the loans of Shylock's victims without charging them interest to repay him. Thisaction has enabled Shylock's victims to escape total ruin, as they pay off their loans to Shylock quickly without having to pay most of the added charges for these loans. Then, they can repay Antonio simply for the amount of their loan. Furthermore, Antonio's action also undercuts Shylock and forces him to lower his interest rates in order to get others to borrow from him.