Halakhah zu Dewarim 5:1

The commandment of Torah study: The positive commandment to study the wisdom of the Torah and to teach it; meaning to say how we should perform the commandments, guard ourselves from that which God prevented us and to also know the laws of the Torah according to their true intention. And about all of this is it stated (Deuteronomy 6:7), "You shall teach them to you sons." And our Rabbis, may their memory be blessed, said (Sifrei Devarim 34:4), "'Your sons' - these are your students. And thus do you find that students are called sons, as it is stated (II Kings 2:3), 'And the sons of the prophets went out.'" And it is [also] said there (Sifrei Devarim 34:1), "'And you shall teach them (shinantam, which sounds like the word for tooth, hence, make them sharp like a tooth)' - they shall be ordered in your mouth, so that if a person questions you [concerning them], you will not stammer to him, but answer him forthwith." And this commandment is repeated in many places, as it is stated (Deuteronomy 5:1), "and study them and do them," "and in order that you will study them" (Deuteronomy 31:12), "and you shall teach them to your children" (Deuteronomy 11:19).

And also from the content of the commandment is that which they, may their memory be blessed, said (Kiddushin 30a), "To what extent is a man obligated to teach his son Torah? Rav Yehuda says that Shmuel said, '[Like], for example, Zevulun ben Dan.'" The understanding of [this is that there was] a man in their generation whose name was Zevulun ben Dan, whose father’s father taught him Scripture, Mishnah, Talmud, laws, and homiles (aggadot). And they challenged what they challenged about this in the Gemara, and the resolution was that the obligation is to teach him Scripture - which is Torah - like the father's father of Zevulun did, and even though the father's father of Zevulun ben Dan taught him more. And one who adds upon the obligation of the commandment, like the father's father of Zevulun ben Dan, brings a blessing upon himself. And one who was not taught by his fathers who are obligated in this - such as his father and his father's father - is obligated to teach himself when he is an adult and recognizes the thing, as it is stated (Deuteronomy 5:1), "and study them and do them." And if [both] the father and the son needed to study, and the father does not have [enough] in his hand that they can both study, he always [comes] before his son. But if his son is more understanding than he and his [son's] studies are more [effective], his son precedes him. And until when is every man obligated to study Torah? Until the day of his death, as it is stated (Deuteronomy 4:9), "and lest they be diverted from your heart, all of the days of your life" (Mishneh Torah, Laws of Torah Study 1:10). And the Sages emphasized the matter more by way of ethics and to teach people desire [for it] and said (Shabbat 83b) that even at the time of death, a man is obligated to study Torah, as it is stated (Numbers 19:14), "This is the law of the Torah, when a man dies in a tent." And everyone in Israel is obligated about the study of Torah (Yoma 35b) - whether poor or rich, whether healthy or one with afflictions. And they, may their memory be blessed, already said (Eruvin 54a) that all of the limbs are healed by involvement in Torah. And even a poor person that goes around to [other people's] doors, and even a married man with children - everyone - is obligated to set time for Torah [study] during the day and during the night, as it is stated (Joshua 1:8), "and you shall meditate about it day and night."