This is still on the online Insight Book.
Insight BookROD, STAFFUses. Rods or staffs were used...to punish children, slaves, or others (Ex 21:20 [“stick,” NW]; Pr 10:13; 23:13, 14; Ac 16:22)Parental authority.
“Rod” is used also to symbolize the authority of parents over their children.
The book of Proverbs makes many references to this authority, the term symbolizing all forms of discipline used, including the literal rod used for chastisement.The parent is actually responsible before God to exercise this rod, controlling the child.If the parent fails in this, he will bring ruination and death to his child and disgrace and God’s disapproval to himself also. (Pr 10:1; 15:20; 17:25; 19:13)“Foolishness is tied up with the heart of a boy; the rod of discipline is what will remove it far from him.”“Do not hold back discipline from the mere boy. In case you beat him with the rod, he will not die. With the rod you yourself should beat him, that you may deliver his very soul from Sheol itself.” (Pr 22:15; 23:13, 14)
In fact, “the one holding back his rod is hating his son, but the one loving him is he that does look for him with discipline.”—Pr 13:24; 19:18; 29:15; 1Sa 2:27-36.
http://m.wol.jw.org/en/wol/d/r1/lp-e/1200003754#h=4