Proverbs 13:24
"He that spareth his rod hateth his son: but he that loveth him chasteneth him betimes."
Cross References (ranked by relevance)
Correct thy son, and he shall give thee rest; yea, he shall give delight unto thy soul.
The rod and reproof give wisdom: but a child left to himself bringeth his mother to shame.
Chasten thy son while there is hope, and let not thy soul spare for his crying.
Foolishness is bound in the heart of a child; but the rod of correction shall drive it far from him.
For whom the LORD loveth he correcteth; even as a father the son in whom he delighteth.
But he that sinneth against me wrongeth his own soul: all they that hate me love death.