Rashi brings the explanation of the Sages for the repetition of "Say" and again "you shall say to them." "It is intended to admonish the adults about their children also - that they should teach them to avoid defilement."

In other words, the fathers were commanded to teach their children to follow in their path of obeying the commandments of the Torah.

Every good educator will attest to the fact that the best, and perhaps the only, way to properly train a child is by personal example. One student once explained why he does not respect his father: "He can shout at me hysterically how terrible it is to be angry!"

The Gaon, Reb Moshe Mordechai Shulzinger, shlita, told a story about a father, who was not much of a Torah learner, who was trying to impress upon his young son the virtue of learning diligently. In the middle of his discourse, he realized that the seven o' clock news was on. In Israel, even doctors, in the midst of minor surgery, take a break to hear this important, extended news broadcast. This father, too, excused himself and went to listen to the radio. After the news was over, he continued to reprimand his son about the importance of Torah learning which surpasses everything else in the world. The young boy, who was more than a bit spunky, asked his father, "Dad, don't you think that my problem just may be hereditary?"

I once heard a fantastic story.

Two brothers had sons. Both brothers loved to learn Torah but one of them did it all day long while the other was a businessman who had a seder to learn every night which he kept punctually. The strange thing was, though, that the sons of the businessman became religious Torah scholars while the sons of the Torah scholar did not.

Brokenhearted, the Torah scholar went to a Gadol to ask how it was that his brother, who only learned an hour or two each evening, was privileged to have such fine sons while he, who learned Torah all day long, was not.

The Gadol replied that although he learned Torah all day long, he never succeeded in passing this love of Torah on to his children, though he spoke about it often, because they never actually saw him learning in practice since he went off to learn before they arose in the morning and returned late at night after they had gone to sleep. The brother, on the other hand, rushed to go to learn as soon as he returned home from work, and his sons actually saw how dear Torah learning was to him. Consequently, they followed the good example he had set for them.

Let us be careful to always act the way we want our children to, and then we will have real nachas from them in this world and in the World-to-Come.