Mishnayos Avos Perek 2 Mishnah 2

"Worldly occupation (derekh erets, literally the way of the world)": A craft or business.

"For the exertion [expended] in both of them causes sin to be forgotten": As Torah [study] dulls the strength of a man and work pulls apart and breaks the body, and as a result of this the evil impulse is rendered idle for him.

"And all [study of the] Torah in the absence of a worldly occupation": And if one might ask, let him work in Torah [study] and its exertion will cause sin to be forgotten, therefore it is required to say, "all [study of the] Torah in the absence of a worldly occupation comes to nothing in the end." As it is impossible for him without food, and [so] he will rob the creatures and forget his study.

"let them work for the [sake of the] name of Heaven": and not in order to take a crown [for themselves], to say, "I did such and such for the community."

"for the merit of their ancestors sustains them": For the merit and righteousness (tsidkatan) of the ancestors of the community - which stands forever - sustains those that work with them, to bring their righteousness to the fore. And it is not from the angle of the efforts of those that work [for the community].

"And as for you [who work for the community], [God says:] I credit you with a reward": Even though the thing does not come to a good end from the angle of your deeds but rather because of the merit of the ancestors of the community, "I credit you with a reward" as if you had accomplished this salvation in Israel, as a result of your doing it for the sake of Heaven. A different explanation: All who are involved with the community to force and coerce the community for the matter of a commandment - for charity or the ransom of captives - let them do it for the sake of Heaven. As the merit of the ancestors of the community will sustain them to give that which they have assigned them, and even if it is much money, and [the merit of] the charity (tsedekah) will endure for them forever. And for you that are involved with them to coerce the community to [do] this commandment, I credit you the reward as if you actually done this commandment with your own money. And Rambam explained, "And as for you [who work for the community], [God says:] I credit you with a reward... as if you had done it" - If at the time that they were involved with the community, they were prevented from the fulfillment of a commandment on account of community matters, I credit you reward as if you had done that commandment from which you were prevented.