Комментарий к Берешит 42:10

לא אדני NAY, MY LORD — do not say this, for behold ועבדיך באו לשבר אכל THY SERVANTS HAVE COME TO BUY FOOD.

ויאמרו אליו לא אדוני, They said to him: "No sir, etc." They said; 1) There is no reason to suspect us of spying even if we had come without a specific purpose. [I believe the author derives this from the tone-sign tipcha under the word באו; we would have expected the tone-sign mercha Ed.] 2) "In fact your servants have come to purchase food." They presented the purpose of their presence to buy food as the most natural explanantion for their journey to Egypt.

ועבדיך, the letter ו at the beginning of this word substitutes for the word אבל, “but”. In other words: “no my lord, not as you have said; but your servants simply came here to buy food.” The use of the letter ו instead of the word אבל is not unique, as it also occurs in Psalms 7,5 ואחלצה צוררי ריקם, “but I have rescued my foe without reward.”

Do not say this (לא תאמר כן)... Rashi added in the wordsתאמר כן (say this) because Yoseif had declared them as spies, so the proper word [to deny this] would be אַל. So we see with Channah (Shmuel I, 1:16). Eli thought she was a drunk, and she replied [in denial]: אַל תתן אמתך לפני בת בליעל. Whereas לא [when standing alone] is the proper reply to a question or a request.

Rather, “Your servants have come to buy food.” This statement is not a proof [that they are not spies, which we see] because Yoseif replied, “No, rather, you have come to spy the land.” This is what the verse means: Do not say this. Rather, [the point is that] your servants have come to buy food. It is like saying אבל עבדיך.