Notice that this passage tells us that Jesus used parables so that certain Jews wouldn't believe and be forgiven. But why? If Calvinists assumption, that men are born unable to believe in Christ without an effectual calling, is true, then why would Christ need to hide the message in parables to prevent them from believing? Jesus must have believed that they could have believed and "returned" to Him, otherwise why would he say this? In short, why would you hide a message from people so they can't believe it when those people were born unable to willingly believe or even understand that message in the first place?