Bámidbár / Szimán jáfe lemisnáto

from the age of thirty years up to the age of fifty, all who were subject to duties of service and porterage relating to the Tent of Meeting—

This is the rule for the Levites. From twenty-five years of age up they shall participate in the work force in the service of the Tent of Meeting;

The baraita notes that one verse states: “From twenty-five years old and upward” (Numbers 8:24), and one verse states: “From thirty years old and upward” (Numbers 4:47). It is impossible to say thirty, as twenty-five is already stated, and it is impossible to say twenty-five, as thirty is already stated. How can these verses be reconciled? Twenty-five years old is the time for apprenticeship and thirty for service.

From here it is derived that a student who did not see a positive indication in his studies after five years will no longer see a productive result from those studies. Rabbi Yosei says that the period is three years, as it is stated with regard to Daniel and his cohort who instructed the king of Babylonia: “And they should be raised three years” (Daniel 1:5), “and he should teach them the books and the language of the Chaldeans” (Daniel 1:4).

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Rabbi Judah said: an unmarried man must not tend cattle, nor may two unmarried men sleep together under the same cover. But the sages permit it. One whose business is with women must not be alone with women. And one should not teach his son a woman’s trade. Rabbi Meir says: one should always teach his son a clean and easy profession, and pray to Him to whom wealth and property belong. For a profession does not contain [the potential for] poverty and wealth, for poverty is not due to one’s profession nor is wealth due to the profession, but all depends on merit. Rabbi Shimon ben Elazar says: have you ever seen a wild beast or a bird with a profession? Yet they are sustained without trouble. Now, were they not created only to serve me, while I was created to serve my master: surely then I should make a living without trouble! But my evil acts have done me in and withheld my livelihood. Abba Gurion a man of Sidon says in the name of Abba Guria: one should not teach his son [to be] a donkey-driver, camel-driver, wagon-driver, sailor, shepherd, or shopkeeper, because their profession is the profession of robbers. Rabbi Judah says in his name: most donkey-drivers are wicked, while most camel-drivers are worthy men; and most sailors are pious. The best of doctors are destined for Gehenna, and the worthiest of butchers is Amalek’s partner. Rabbi Nehorai says: I will abandon every profession in the world and I will not teach my son anything but Torah, for a person enjoys its reward in this world while the principal remains for him in the world to come. But all other professions are not so; for when a man comes to sickness or old age or suffering and cannot engage in his profession, he must die of starvation, whereas the Torah is not so, for it guards him from all evil in his youth and gives him a future and hope in his old age. Of his youth what is said? “But they that wait upon the Lord shall renew their strength” (Isaiah 40:31). Of his old age what is said? “They shall still bring forth fruit in old age” (Psalms 92:15). And it is also said of our father Abraham, “And Abraham was old … And the Lord blessed Abraham with everything” (Genesis 24:1). We find that Abraham our father observed the whole Torah before it was given, for it is said, “Because Abraham obeyed My voice, and kept My charge, My commandments, My statutes, and My laws” (Genesis 26:5).

Every man has a preference for a particular work or business over others. G-d has already implanted in his nature a love and fondness for it, as He implanted in a cat's nature the hunting of mice, or the falcon to hunt smaller birds, the deer to trap snakes. Some birds hunt only fish, and likewise, each animal species has a liking and desire for particular plants or animals, which G-d has implanted to be the means for its sustenance, and the structure of its body and limbs is suited for that thing. The long bill and legs of a fish catching bird, or the strong teeth and claws of the lion, horns of the ox and ram (i.e. for defense - TL), while animals whose sustenance is from plants do not have the tools to hunt and kill.