“for there is.” Although many versions treat the Hebrew as a temporal phrase, “Discipline…while there is hope,” the Hebrew text does not support that interpretation (Waltke; Proverbs). Furthermore, the Hebrew word muth (#04191 מוּת), death, is in the hiphil aspect, which is a causative action in the active voice, “to put to death.” There are times when children are such a disappointment that parents give up on them, and in the OT culture a child who was ruining the family could be executed (Deut. 21:18-21). Here is an exhortation to parents not to give up on even unruly children, but to exert an effort to discipline them and bring them back to a right path.
“long in your soul.” The Hebrew contains an idiom, and literally reads, “lift up your soul.” To lift up the soul to something is to desire it or to aspire to it. No parent would “long for” or even desire in any way, their child to die. Thus, this verse is a type of hyperbole in which if a parent does not have the godly love and resolve to discipline a child, it is as if the parent were longing for the child to die. A child who is not disciplined will become a fool and a disgrace (Prov. 22:15; 29:15).