Midrash su Salmi 109:6

And God said unto Jacob: “Arise, go up to Beth-El” (Gen. 35:1). May our master teach us: How many times is a man’s “account book”⁷The heavenly ledger wherein man’s deeds are recorded. open? Thus did our masters teach us: A man’s account book is opened three times: when he journeys alone upon a highway; when he resides in a dilapidated house; when he vows and fails to fulfill. R. Aha the son of Jacob deduced the first statement from the biblical verse If harm befall him by the way (Gen. 42:3). R. Eliezer the son of R. Yosé the Galilean stated: If you should discover that a righteous man is setting out on a journey, leave even three days earlier or three days later in order to travel with him. But if you should see a wicked man setting out on a journey, leave three days earlier or three days later in order not to go with him, as it is said: Set thou a wicked man over him; and let an adversary stand at his right hand (Ps. 109:6). A righteous man, however, is accompanied by angels of peace, as it is said: For He will give his angels charge over thee (ibid. 91:11).

How did Jacob know when to go in to his father so that Esau would not precede him and receive the blessing? As soon as Esau went out to hunt, the Holy One, blessed be He, sent Satan after him to keep him from catching anything until Jacob had received the blessing, as it is said concerning Esau: Set thou a wicked man over him, and let an adversary stand at his right hand (Ps. 109:6).