The fear of the Lord is used in two different senses in the Word of God: For believers, the fear of the Lord is such an awe, reverence, and love for the Lord God that they depart from evil - that they desire to turn from sin and also get any sin right that they have allowed to come into their lives. To the lost, the fear of the Lord is more a terror, a dread, such a fear of His power and His judgment that they are overwhelmed. (See 2 Corinthians 5:11.) Better to trust the Lord for salvation, and then have the only fear in your life that pleases Him: the fear of the Lord.
Proverbs 16:6 By mercy and truth iniquity is purged: and by the fear of the LORD men depart from evil.
In Genesis 34, we have the story of Jacob's daughter, Dinah, and her fornication with Shechem, a lost man. When her family found out what had happened, they were understandably upset.
Genesis 34:1-5 And Dinah the daughter of Leah, which she bare unto Jacob, went out to see the daughters of the land. And when Shechem the son of Hamor the Hivite, prince of the country, saw her, he took her, and lay with her, and defiled her. And his soul clave unto Dinah the daughter of Jacob, and he loved the damsel, and spake kindly unto the damsel. And Shechem spake unto his father Hamor, saying, Get me this damsel to wife. And Jacob heard that he had defiled Dinah his daughter: now his sons were with his cattle in the field: and Jacob held his peace until they were come.
Shechem and his father sought to make marriage alliances with Jacob and his family: Shechem would marry Dinah, and their two families/people would be united through further intermarriage with one another.
Genesis 34:6-8 And Hamor the father of Shechem went out unto Jacob to commune with him. And the sons of Jacob came out of the field when they heard it: and the men were grieved, and they were very wroth, because he had wrought folly in Israel in lying with Jacob's daughter; which thing ought not to be done. And Hamor communed with them, saying, The soul of my son Shechem longeth for your daughter: I pray you give her him to wife.
Jacob's sons agree deceitfully, and exhort the men of Hamor's household to circumcise themselves first before this alliance can be completed. (See verses 9-17.)
Genesis 34:18-19 And their words pleased Hamor, and Shechem Hamor's son. And the young man deferred not to do the thing, because he had delight in Jacob's daughter: and he was more honourable than all the house of his father.
Though Shechem had done wrong in lying with Dinah, he sought to do right by taking her as his wife. When given the conditions to make this a reality, he didn't hesitate or procrastinate - even though circumcision would have been a painful thing for adult men to undergo.
While Hamor's people were sore and recovering from their circumcisions, Levi and Simeon went into the city and slaughtered all the men, taking their livestock, taking the women and children captive, and spoiling the city. (See verses 20-29.) As a result, fear of reprisal came upon Jacob:
Genesis 34:30-31 And Jacob said to Simeon and Levi, Ye have troubled me to make me to stink among the inhabitants of the land, among the Canaanites and the Perizzites: and I being few in number, they shall gather themselves together against me, and slay me; and I shall be destroyed, I and my house. And they said, Should he deal with our sister as with an harlot?
Jacob was suddenly distraught by the fear of man - until the Lord spoke to him, and told him what to do.
Genesis 35:1 And God said unto Jacob, Arise, go up to Bethel, and dwell there: and make there an altar unto God, that appeared unto thee when thou fleddest from the face of Esau thy brother.
In effect, he was told to go back to where he first knew the Lord, where he first walked with Him. Go to Bethel (which means "house of God"; see Genesis 28:17, 19), dwell there, and make an altar to God.
Basically God was saying, Put your eyes back on Me, Jacob. He realized that he and his family had not been walking with the Lord the way they should have been - and knew there was some business he needed to take care of first!
Genesis 35:2-5 Then Jacob said unto his household, and to all that were with him, Put away the strange gods that are among you, and be clean, and change your garments: And let us arise, and go up to Bethel; and I will make there an altar unto God, who answered me in the day of my distress, and was with me in the way which I went. And they gave unto Jacob all the strange gods which were in their hand, and all their earrings which were in their ears; and Jacob hid them under the oak which was by Shechem. And they journeyed: and the terror of God was upon the cities that were round about them, and they did not pursue after the sons of Jacob.
Due to their compromises, Jacob's family had allowed themselves to be influenced either by Laban's household or by the people of the land of Canaan, and had allowed idolatry to take a foothold in their own household. Out of the fear of the Lord, Jacob made his family put away all of their idols and to cleanse themselves - which included changing their garments, and removing their earrings (the implication here being that these earrings had a direct association with idolatry).
2 Corinthians 7:1 Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.
When Jacob and his family repented, the Lord put His terror upon the cities round about Jacob's family, and God gave them complete safety from their enemies. God delivered Jacob and his family because they ordered their conversation (ie. manner of living) right:
Psalms 50:23 Whoso offereth praise glorifieth me: and to him that ordereth his conversation aright will I shew the salvation of God.
Proverbs 14:27 The fear of the LORD is a fountain of life, to depart from the snares of death.
Job 28:28 And unto man he said, Behold, the fear of the Lord, that is wisdom; and to depart from evil is understanding.