Charles Ellicott Commentary Genesis 34:1

"And Dinah the daughter of Leah, whom she bare unto Jacob, went out to see the daughters of the land." — Genesis 34:1 (ASV)

Dinah ... went out to see the daughters of the land. —Those commentators who imagine that Jacob lived only twenty years at Haran must assume that he remained two or more years at Succoth, and some eight years at Shechem, before this event occurred, leaving only one more year for the interval between Dinah’s dishonour and the sale of Joseph to the Ishmaelites.

Nevertheless, if Dinah was now not more than fourteen, there would remain a period of only nine years, in which Leah had to bear six sons and a daughter, with a long interval of barrenness, during which Zilpah was given to Jacob and bore two sons.

But besides this impossibility, Jacob evidently remained at Succoth only until he was shalem, sound and whole from his sprain. Dinah’s visit was one of curiosity, for she went to see the daughters of the land. That is, she wanted, as Abravanel says, to see what the native women were like and how they dressed themselves.

Josephus says that she took the opportunity of a festival at Shechem. However, as neither her father nor brothers knew she was going, but were with their cattle as usual, it is likely that with only one or two women she slipped away from her father's camp and paid the penalty of her girlish curiosity. But she would feel no such curiosity after being a year or two at Shechem, so it is probable that her dishonour took place within a few weeks after Jacob’s arrival there.

Similarly, Hamor’s words in Genesis 34:21-22 clearly show that Jacob was a newcomer. For he proposes that the people should let them dwell in the land, and therefore consent to the condition required by them that the Hivites should be circumcised. It would have been absurd to speak this way if Jacob had already lived there eight years with no apparent intention of going away.