He has an economic and social objection. The Pharaoh makes the people work hard because otherwise they will become too big a nation (see Exodus 1:9–11). This succeeds only partially, because the work is done, but the people do not get smaller (Exodus 1:12). Now Pharaoh will not allow the leaders, Moses and Aaron, to keep their people from doing the work. The work itself is also valuable to him.
5 And Pharaoh said, “Behold, the people of the land are now many, and you make them rest from their burdens!”