(Devarim 23:25) "If you come into the vineyard of your neighbor, you may eat grapes so as to satisfy your soul": "If you come into the vineyard of your neighbor": I might think (that the verse speaks of) any man (who enters the vineyard); it is, therefore, written (Ibid.) "but into your vessel you shall not pace them." (You shall place them, however,) into the vessels of the owner, (for whom you are working).
"your neighbor": but not a gentile. "your neighbor": but not the Temple.
"you may eat," but not suck (out the wine and discard the rest, [for this would result in his eating a greater number of grapes]).
"grapes": and not figs — whence it was ruled: If he were working with (i.e., picking) grapes, he should not eat figs; if he were working with figs, he should not eat grapes. But he should restrain himself until he reaches the choice ones (and then eat).
R. Elazar b. Chasma says: Whence is it derived that a worker may not eat more than his wage? From "so as to sate your soul." And the sages say: "so as to sate," which implies that a worker may eat even more than his wage.
"but into your vessel you may not place them": when you are placing them into the vessel of the owner.