Ok so I warn you...I'm about to go slightly Bible Nerd!
Many people use the phrase "spare the rod and spoil the child" as clear evidence that the Bible wants parents to spank their children. BUT...this is not a Bible verse. Just like "God helps those who helps themselves" and "cleanliness is next to Godliness" are not Bible verses.
The phrase "spare the rod and spoil the child" actually comes from the poem "Hudibras" written in 1664 by Samuel Butler. In it he writes:
"What medicine else can cure the fits
Of lovers when they lose their wits?
Love is a boy by poets styled
Then spare the rod and spoil the child"
The poet is actually comparing women to children and explaining that they need to be spanked in order for their love to grow and that lack of spanking them will "spoil" the relationship.
Now it is true that the Bible talks about spanking your children as a way to discipline but it also speaks about not provoking them to wrath in Ephesians 6:4, and about guiding and directing them much as a shepherd does his sheep, with no mention of spanking or hitting. The shepherds job was to keep the sheep safe and to keep them on the right path, much like our job as parents.
Spanking is a good tool, rather a swat then a hand burnt on the stove, or a kid running into traffic (especially if that child is too young to reason with). But spanking is not and should not be the only tool that we use. Spanking alone does not prepare a child for life as an adult. Even after you spank your child, if you decide to discipline that way, you should always use it as an opportunity to teach them. Even if they are young, explain to them what they did wrong and let them know what is expected of them to keep them safe and out of trouble.
Most of our stories and life lessons we teach our kids are from the Bible or adaptations of Biblical principles. Some just get misconstrued over the years.