Hitting one another is a human thing, so much so that we've tried to take a Bible verse (Proverbs, literally "a proverbial saying;" more on that in a moment) about shepherding/guiding sheep and turn it into a justification for laying a violent hand on our children.
Now, before someone jumps on me for misinterpreting the Biblical verse, take a moment to read through all the English versions of the verse (and if you speak another language, read them, too): Proverbs 13:24
In all these verses, I see nothing about "punishing" or "punishment." I see "chasten" and I see "discipline." Let's compare the three words:
Chasten: To restrain; subdue.
Discipline: to train by instruction and exercise; drill.
Punish: to subject to pain, loss, confinement, death, etc., as a penalty for some offense, transgression, or fault.
Now, of those three, which one sounds most inclined towards raising a hand (whether in anger or disappointment) against someone too small to protect themselves?
Many people say that the "rod" is in reference to the shepherd's rod or crook, the stick used to guide sheep. And while that rod is often used roughly (to hook around a wandering sheep's neck and jerk him back into place, for example), it is never used to beat a sheep into submission (unless the shepherd in question has some serious problems).
But all of this is simply coming from a proverbial saying. It would be like taking as instruction, "A bird in the hand is worth two in the bush." And while this is good advice to keep in mind, it does not literally mean you should walk around with a bird held in your hand.
All of this simply to say: I am choosing a gentler form of discipline. Children learn behavior from adults. How hypocritical is it to tell your child, "Don't hit!" and then swat them (whether on the tush, the hand, the arm, the shoulder... whatever body part you choose, it is still hitting).
And lest we forget:
Hit: to deal a blow or stroke to.
Sounds like a spanking to me.
There are boundless books dealing with non-violent discipline for children, and I am currently reading them as fast as I can. Because I find myself often getting frustrated with the Baby Beast for being a normal toddler and getting into everything, and wanting to do things his own way, and wanting to explore. Here are the ones I recommend:
Unconditional Parenting by Alfie Kohn
Playful Parenting by Lawrence Cohen
I have read or am reading those. Books that I have on my list of To Read include:
The Natural Child by Jan Hunt
The Happiest Toddler on the Block by Harvey Karp
I hope that some of these will be useful to you; they certainly have been for me.
You may ask how gentle discipline fits in with natural parenting, since humans have almost certainly been smacking each other since the days when they were pre-humans who looked more like apes than modern man. What is more natural than respecting another human being as a human being? After all, while the Baby Beast is my baby, he is also another person who will someday be making his own life choices. Do I want him to have a firmly rooted base in using violence to end disputes, or would I rather him be able to reason through things and talk about problems? To me, that's a no brainer.
And all that is besides the perk of having a happy, secure toddler.