Verse 12b (“lest they should turn and be forgiven”) looks hard. It looks as though Jesus wants to prevent some people from receiving grace. However, this clause is dependent on verse 12a. Why did the people not want to see and understand? Because they reject the required conversion and the proffered grace. To avoid them, they must look at and listen to Jesus’ work only superficially. And since that is indeed what they do, for his part Jesus also creates a distance in his speaking: they receive what they want (images that leave them free to choose). When Jesus uses the form of instruction of the parables, he responds to the distance that the outsiders very intentionally want to observe. And he hands them over to the distance they themselves chose. Those who want to remain outside are now being treated as outsiders. They receive what they want and the forgiveness of sins through Jesus is withheld from them and leaves them alone.1
12 so that “they may indeed see but not perceive, and may indeed hear but not understand, lest they should turn and be forgiven.”