Midrash su Salmi 91:7

Behold, I send an angel before thee (Exod. 23:20). Scripture says elsewhere in reference to this verse: For He will give His angels charge over thee, to keep thee in all thy ways (Ps. 91:11). When a man performs one precept, one angel is assigned to guard him; when he performs two precepts, two angels are given to him; when he performs all the precepts, many angels are assigned to him, as it is said: For He will give His angels charge over thee. Who are these angels? They are the beings who will protect him from demons, as it is said: A thousand may fall at thy side, and ten thousand at thy right hand (ibid., v. 7). What is meant by may fall? It means that they force (their opponents) to surrender to him, as it is said in the Book of Chronicles: Of Manasseh also there fell away some to David (I Chron. 12:20), and it is written as well: As he went to Ziklag, there fell to him of Manasseh (ibid., v. 29).

Jacob rose up early in the morning in great fear, and said: The house of the Holy One, blessed be He, is in this place, as it is said, "And he was afraid, and said, How dreadful is this place ! this is none other but the house of God" (Gen. 28:17). Hence thou canst learn that every one who prays in Jerusalem is (reckoned) as though he had prayed before the Throne of Glory, for the gate of heaven is there, and it is open to hear the prayers of Israel, as it is said, "And this is the gate of heaven" (ibid.).

And Jacob fell upon his face to the ground before the foundation stone, and he prayed before the Holy One, blessed be He, saying: Sovereign of all worlds ! If Thou wilt bring me back to this place in peace, I will sacrifice before Thee offerings of thanksgiving and burnt offerings, as it is said, "And Jacob vowed a vow, saying" (Gen. 28:20). There he left the well, and thence he lifted up his feet, and in the twinkle of the eye he came to Haran, as it is said, "And Jacob went on his journey, and came to the land of the children of the east" (Gen. 29:1); and the (text) says, "And Jacob went from Beer-Sheba, and went to Haran" (Gen. 28:10). "And the Holy God is sanctified in righteousness" (Isa. 5:16). The angels answered and said: Blessed art Thou, O Lord, the Holy God.