A person should think to himself, if G-d forbid he had a child who did not speak, he would surely spend time, money, and effort to heal him. Yet even though a person knows that in the World to Come there is only Torah, and if a person did not learn Torah he will not be able to say anything at all, he neglects to ensure his children will have this power of speech. If they do not learn, they will be silent not only for a day or two, but will be silenced for eternity, and will suffer from it terribly. So a person should invest extra effort to teach his children Torah, and thorough this he will earn true eternal honor and glory.