Felix carried a real grudge against Jonathan the high priest. He was bitter about the priest’s frequent admonitions to be a better governor. And as Josephus recorded this story he commented that "incessant rebukes are annoying to those who choose to do wrong." So Felix paid a great sum to certain evil men to get Jonathan killed. These thugs went into the temple grounds as if to worship, but carried daggers beneath their cloaks. They mingled with the people around Jonathan, then murdered him in broad daylight. Delivering admonitions, warnings, or rebukes can get you into real trouble!
The Greek word for this kind of admonition or warning is nouthesia (noo theh SEE ah). In the New Testament the same word is often translated instruction. The Kittel article on this word says, "It presupposes an opposition which has to be overcome. It seeks to correct the mind, to put right what is wrong, to improve the spiritual attitude." That can be a big job—and it is best begun when the person on the receiving end is still young.
Paul told fathers to bring up their children "in the discipline and instruction of the Lord" (Eph 6:4). (Many versions translate this "discipline and admonition.") However we choose to translate the word, the command in this verse is not about teaching little ones to count or to read. It is mainly about correction.
Teaching has its primary effect on the intellect; instruction has its effect on the will and the disposition. Teaching is about adding information and skill; instruction is about correcting wrongheadedness. Teaching is about watering the garden; instruction is about weeding.
It is often observed that kids don’t have to be taught to be bad; they have to be taught to be good. That's why they need instruction.