Read Mark 4:12 Using Other Translations
That seeing they may see, and not perceive; and hearing they may hear, and not understand; lest at any time they should be converted, and their sins should be forgiven them.
so that "they may indeed see but not perceive, and may indeed hear but not understand, lest they should turn and be forgiven."
so that the Scriptures might be fulfilled: ‘When they see what I do, they will learn nothing. When they hear what I say, they will not understand. Otherwise, they will turn to me and be forgiven.’ ”