“Spare the rod and spoil the child” is the oft-quoted phrase attributed to the Bible that endorses corporal punishment. Did you know this phrase does not specifically come from the Bible? It’s actually attributed to a 17th-century satirical poem by Samuel Butler entitled “Hudibras.” Of course, his usage of the phrase is obviously derived from the Biblical passage Proverbs 13:24, “Whoever spares the rod hates his son, but he who loves him is diligent to discipline him. Didn’t catch that? This explains it.”
Proponents of physical discipline in particular like to justify their methods by citing that passage. A closer reading, however, reveals that it may not be so straightforward. Of course, by the time of the 1600s and Samuel Butler’s poem, use of a rod is going to entail delivering a beating. However, in Biblical times a position of authority within a tribe of Hebrews would have been signified by a scepter or staff. It was the symbol of power. To that end, we could interpret the Biblical passage as similarly symbolic. Loving your son requires the diligence to enact discipline, but this is through the use of the rod. The rod, in this case, could easily mean the symbolic authority of the father. Sparing the rod here would entail failing to use that authority to properly discipline.
Considering that other passages in Proverbs were clearly symbolic -23:5 details riches sprouting wings and taking flight- we can safely assume that the 13:24 passage is symbolic, as well. This makes the endorsement for corporal punishment significantly less clear-cut.