A man should first study Torah and then marry, because if he marries first he will not be free to focus on his studies. If his desires prevent him from concentrating on his studies, he should marry first and then study Torah (Rambam Mishneh Torah, Sefer HaMadda, Hilkhot Talmud Torah 1:5). Some claim that as a man is obligated to know the entire Torah and to not forget any of it, he could theoretically spend his entire life studying Torah and never marry. This approach is not suitable for everyone, and as the mitzva of procreation has been described as “greater than all the mitzvot” and it is impossible to have another fulfill this mitzva on one’s behalf, it is proper to marry after studying all the halakhot of the Torah and their reasons in brief (Shulĥan Arukh HaRav 3:1; Kuntres Aĥaron on Shulĥan Arukh HaRav 3:1).

The basic mitzva is for one to teach his son the entire Written Torah, or to hire a teacher to do so (Rambam Mishneh Torah, Sefer HaMadda, Hilkhot Talmud Torah 1:7). This minimal requirement is in effect even if the father is occupied with earning a livelihood, but if he has the ability, he must teach his son Mishna, Talmud, halakhot, and aggadot (Tur).