Sifrei Devarim 266

כי תבא בכרם רעך. יכול לעולם? תלמוד לומר "ואל כליך לא תתן", בשעה שאתה נותן לכליו של בעל הבית.

(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).

רעך. פרט לעובדי כוכבים. רעך. פרט לגבוה.

"your neighbor": but not a gentile. "your neighbor": but not the Temple.

ואכלת. ולא מוצץ.

"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]).

ענבים. ולא תאנים. מכאן אמרו, היה עושה בענבים לא יאכל בתאנים, בתאנים לא יאכל בענבים. אבל מונע עצמו עד שמגיע למקום היפות ואוכל.

"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).

ר' אלעזר (בן) חסמא אומר, מנין שלא יאכל פועל יותר משכרו? ת"ל "כנפשך". וחכ"א "שבעך", מלמד שאוכל פועל יותר על שכרו.

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.

ואל כליך לא תתן. (אפילו) בשעה שאתה נותן לתוך כליו של בעה"ב.

"but into your vessel you may not place them": when you are placing them into the vessel of the owner.