There is a large gap when it comes to religion. The subsample on religion has been included in the GSS only occasionally, yet there is a clear divergence. Born-again Christians are, on average, 15 percentage points more likely than the rest of the population to agree that spanking is an acceptable form of punishment.
Amanda Marcotte expands on the religious angle:
Christian conservatives defend the practice of spanking children, even with weapons, by saying that parents are not supposed to do so in anger.
“You want to be calm, in control, and focused,” writes Chip Ingram of Focus on the Family and that a parent who embraces corporal punishment “is not an angry, insensitive person with a big club and a vicious agenda.” This echoes a common refrain from parents to justify spanking, that they don’t do it in anger and they reserve it for serious infractions that require a lot of time and processing so the child doesn’t do it again.
Unfortunately, parents are overestimating their own abilities to keep it in check. Researchers at Southern Methodist University strapped audio recorders onto the arms of 33 mothers to see if and when they used spanking, and found that instead of retreating to a quiet space to calmly administer a spanking, mothers who spank are just hitting in anger and frustration. Kids got spanked for finger-sucking, messing with pages of a book, or getting out of a chair when they weren’t supposed to. Parents who spank say they do so around 18 times a year, but the SMU researchers found it was closer to 18 times a week.