במדבר כ:יז פירוש: רש״י, ספורנו, רשב״ם וטור הארוך

נעברה נא בארצך LET US PASS, I PRAY THEE, THROUGH THY COUNTRY — You have no right to lay claim to the land of Israel as an inheritance, just the same as you have not paid the debt (see Rashi v. 14); render us therefore a little assistance by permitting us to pass through your land.

דרך המלך, the route which the king would command them to travel. It was an established custom that when foreign armies were given permission to traverse a neutral country’s territory that they were assigned a specific route for that purpose. Such armies would also be assigned a guide advising them of possible pitfalls en route.

ולא נשתה מי באר, water from your wells. Water was very precious and hence expensive in that land.