C. F. Keil and Franz Delitzsch on Genesis 40:1-4

Gen 40:1-4

The head cup-bearer and head baker had committed crimes against the king of Egypt, and were imprisoned in “the prison of the house of the captain of the trabantes, the prison where Joseph himself was confined;” the state-prison, according to Eastern custom, forming part of the same building as the dwelling-house of the chief of the executioners. From a regard to the exalted position of these two prisoners, Potiphar ordered Joseph to wait upon them, not to keep watch over them; for את פּקד does not mean to appoint as guard, but to place by the side of a person.