If Pharaoh was concerned about the Israelites' joining with Egypt’s enemies, would it not be better if they left Egypt? Otherwise, they would pose a threat from within. Based on this, Stuart has suggested that the phrase should be translated as take possession of the land.
1 In other words, Pharaoh is concerned that Israel might take over Egypt. However, this conclusion is not supported by the Hebrew, which should be translated as go up from the land.
Travel from Egypt to Canaan is often characterized as going up
and travel from Canaan to Egypt as going down
(Genesis 12:10; Genesis 13:1; Genesis 26:2; Genesis 37:25; Genesis 39:1; Genesis 42:2–3; Genesis 43:15; Genesis 45:9, Genesis 45:25; Genesis 46:3–4; Genesis 50:14, Genesis 50:24; Exodus 3:8, Exodus 3:17). The wording indicates that Pharaoh wants to prevent Israel from returning to Canaan. In this way, his behavior is consistent with the later Pharaoh who stubbornly refuses to let Israel go (Exodus 5:2, etc.).
On an earthly level, Pharaoh likely had political and economic reasons for this fear. When the Egyptians expelled the Hyksos, they drove them towards Canaan.2 If the Israelites were to ally with the Hyksos and join them in Canaan, Egypt’s enemy would be greatly strengthened. But by keeping them in subjection, Pharaoh could ensure that Israel would serve Egypt’s interests.
10 Come, let us deal shrewdly with them, lest they multiply, and, if war breaks out, they join our enemies and fight against us and escape from the land.”