Exodus 8:28

“And Pharaoh said, I will let you go, that ye may sacrifice to the Lord your God in the wilderness, etc.] He does not say three days, though as he allowed them to go into the wilderness and sacrifice, they could not go and come again in less time; nor would Moses have accepted of the grant, as it seems by what follows he had, if he had obliged them to less time: only you shall not go very far away; his meaning is, as Aben Ezra observes, that they should go no further than three days’ journey; he was jealous that this was only an excuse to get entirely out of his dominions, and never return more. He might have heard of their claim to the land of Canaan, and of their talk, and hope, and…”

“Ye shall not go very far away - Not so far but that he might fetch them back again. It is likely he suspected that if once they left Egypt, they would never come back; and therefore when he is forced to consent that they shall go, yet he is not willing they should go out of his reach. See how ready God is to accept sinners submissions. Pharaoh only says, Intreat for me - Moses promises immediately, I will intreat the Lord for thee; and that he might see what the design of the plague was, not to bring him to ruin, but to repentance. Exodus 8:32”

“I will: Hos 10:2 entreat: Exo 8:8, Exo 8:29, Exo 9:28, Exo 10:17; Kg1 13:6; Ezr 6:10; Ecc 6:10; Act 8:24 Exodus 8:29”