Tafsiran Keluaran 10:8: Rashi, Ramban, Or HaChaim & Tur HaArokh

ויושב [AND MOSES AND AARON] WERE BROUGHT BACK (The verb has a passive meaning [Hophal], not an active as the particle את before משה and אהרן might lead one to suppose) — They were brought back by a messenger: they (Pharaoh’s servants) sent people after them and these brought them back to Pharaoh.

BUT WHO ARE THEY THAT SHALL GO? Pharaoh desired that their leaders, elders, and officers²⁷See Deuteronomy 29:9. should go, men that are pointed out by name.²⁸Numbers 1:17. Moses answered him that also the sons and daughters will go, “for we must hold a feast unto the Eternal,²⁹Verse 9. and it is mandatory upon us all to take part in the feast.” Pharaoh’s anger was then kindled on account of the sons and daughters, and he said that under no circumstances will he send the little ones, for they take no part in the offerings. Instead he would send all the adult males because of the feast which Moses mentioned, while the little ones and the women will remain [in Egypt].

לכו עבדו…מי ומי ההולכים "Go and serve…who are the ones going?" Pharaoh asked a rhetorical question; it had not occurred to him that they would demand that all of them should go. This is why he had simply said: "go and serve" without limiting the ages or sexes of who was included in that offer. He had naturally assumed that only adult males would particpate in the ceremony under discussion. This is why he said later: "your menfolk may go because that is all you ever requested." He did not even want all the adult males to go.