What did Hashem mean when He instructed Yakov to leave, and promised that He would be with him?
Rashi: As long as he remained attached to Lavan (whom Hashem described as Tamei), Hashem's Shechinah would not rest on him, and only after he returned to his father's would it rest on him. 1
Seforno: He promised that He would guard him on the homeward journey. 2
Oznayim la'Torah: Hashem was hinting that, when the Nochrim begin to eye us with an Ayin ha'Ra and to turn against us, it's time to leave.