Psalm 19:9 says, “… the fear of the Lord is pure, enduring forever.” One common translation says, “… the fear of the Lord – keeps me clean.” The ‘fear of the Lord’ was a staple phrase, a component of the Old Testament piety. It was expected. Aquinas saw it as an essential for New Testament believers as well.
The idea that ‘fear’ is associated with Sinai and Law and is dismissed by grace is flawed theology. Isaiah 11:3 had foretold that the Messiah would “delight in the fear of the Lord.” Paul reminds us that the path to depravity begins with the loss of the fear of God, “there is no fear of God before their eyes” (Rom. 3:18, quoting Psalm 36). John Calvin noted:
All wickedness flows from a disregard of God … Since the fear of God is the bridle by which our wickedness is held in check, its removal frees us to indulge in every kind of licentious conduct.
On the cross, we can hear the repentant thief rebuking his dying counterpart, “Do you not fear God?” (Luke 23:40). He didn’t. He was blind. Jesus characterized injustice as rising from a bench occupied by an irreligious judge, who “neither fears God” and he notes the corollary, “nor cares about men” (Luke 18:2). The two are bound together. Restraint, respect for those created in the image of God is possible only if there is respect for the Creator. Dismiss God, and you lose the race of men.
The New Testament Church walked in the fear of the Lord. Luke says, “Then had the churches rest throughout all Judaea and Galilee and Samaria, and were edified; and walking in the fear of the Lord, and in the comfort of the Holy Ghost, were multiplied.” (Ac 9:31)
These people knew it necessary to “live in the fear of the Lord” (Acts 9:31). Christ had risen from the dead – and they were awestruck. They heard the wind and saw the fire in the Upper Room, and they were not the same. The Spirit poured upon the church is noted by Isaiah’s prophecy as the Spirit of Christ, and therefore, the Spirit of the fear of the Lord. John Murray wrote, “The fear of God is the soul of godliness … If we are thinking of the [marks] of biblical piety, none is more characteristic than the fear of the Lord.”
Mary, the mother of Jesus connected mercy and fear, “his mercy extends to those who fear him” (Luke 1:50). Paul said that ‘holiness’ was perfected “in the fear of God” (II Cor. 7:1 RSV), and he urged them to “work out your salvation with fear and trembling” (Phil. 2:12), and also to “be subject to one another in the fear of Christ” (Eph. 5:21 NASB). Peter likewise urged, “love the brotherhood of believers, fear God, honor the king” (1 Pet. 2:17), and “live your lives as strangers here in reverent fear” (1 Pet. 1:17).
Why, how have we lost this sense of deep reverence? It is for certain: this will not be recovered by the culture; this has to be nurtured in the Church.
 John Calvin, “The Epistles of Paul to the Romans and Thessalonians,” Vol. 8; New Testament Commentaries (Grand Rapids: Eerdmans, 1980), 67.
 John Murray, Principles of Conduct, p. 229.