What Does Genesis 42:10 Mean?

They said to him, "No, my lord, your servants have come to buy food." The brothers' immediate denial is the expected defensive response to the spy accusation. "No, my lord": the respectful form of address to an Egyptian official: is followed by the correction of his stated assumption: we are not spies; we are buyers. The claim is true. They have come to buy food. The simplicity and truthfulness of their denial is what makes the spy accusation so difficult to maintain in good conscience: except that Joseph knows the denial is true and is not maintaining the accusation in good conscience but as a test.

The application of "my lord": the same term of deference they will use throughout the Genesis 42 to 44 encounter: signals their complete subordination to the official's authority. They are supplicants, not negotiators. They need the grain; they cannot argue from a position of right or power; they can only appeal to the official's judgment and hope he releases them. The power differential that the accusation establishes is the context of the entire test: they must convince the official of their innocence and reliability without knowing who he is or what he already knows about them.

"Your servants have come to buy food": the self-identification as "servants" is the brothers adopting the social position appropriate to their situation. They are not degrading themselves beyond what the context requires; they are acknowledging the reality of the encounter. The Egyptian prime minister is the lord; they are the foreign petitioners who need what he controls. The language of servitude in their address to Joseph recalls the dreams of Genesis 37 in which the brothers would serve (in the form of bowing to) the dreamer. The dreams are unfolding in plain sight, and the brothers do not know it.