Train up a child in the way he should go: and when he is old, he will not depart from it.
Proverbs 22:6

This is a very well known Scripture verse, especially when we are talking about how to train your children. I have heard a few different ideas of what this verse is teaching, and I think there is validity to each of them. Let's start with the definition of "train up" from the Strong's Exhaustive Concordance:

A primitive root; properly, to narrow (compare chanaq); figuratively, to initiate or discipline -- dedicate, train up.

With that definition in mind, here are two interpretations of this verse that I've heard:

The parents are to train their children in the way they feel is best, according to the Bible. The result will be that the children will stay with what they were trained when they are older. I believe that this is, with some further depth and understanding, the primary teaching of this verse.
The parents are to train their children in the way God is leading that child to be. I have also heard that "the way he should go" should be translated "the way he is bent." I'm in favor of changing the words in Scripture. Sometimes, however, we do need clarification about what the words mean. I believe that there is validity to this truth, although, I don't think the wording of the verse needs to be changed. I'll talk more about this later.

Going back to our definition of "train up," there are several key parts that work together. If one part is left out, I believe that part of the training process is lost.

"To narrow" - Some people think that Christians "brainwash" or "indoctrinate" their children, forcing them to live a severely strict lifestyle. Whether or not you think they take it too far is not the issue. The issue lies more with the fact of teaching their children why they do what they do (what they say, how they act, what they wear, etc.). Being narrow is necessary: it help protect your children, especially while they are young. But as they grow older, they need to learn the reasons behind what they are being taught.
"To initiate" - This part of the definition indicates that training is a life-long process. As parents, we are just starting the process: we're initiating it. The beginning of any teaching is critical, since all teaching afterwards is based on those foundational principles.
"To discipline" - Discipline is more that punishment for wrong doing (which is a common usage of the word). Discipline is to "train (someone) to obey rules or a code of behavior, using punishment to correct disobedience." So the purpose of discipline is to help the other person better understand and follow certain practices, only...

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