Don’t Look Back
The Alshich Hakodesh writes that it would seemingly be proper to mention the eyes before the heart, as one sees something before he desires it in his heart. He answers that the reason the heart is mentioned first is because sometimes a person is walking in the street and he suddenly is confronted with a forbidden sight. In such a case, the image goes into his heart without his eyes even looking for it.
The pasuk therefore says that one should realize that he has to first work on his heart, in order to remove the desire to see such things from within him. If one does this, even if he accidentally sees something wrong, he will turn away and he won’t look a second time. Thus, once the desire is removed from his heart, he won’t look a second time and, therefore, he will not be punished.
