Job 19:29 Be ye afraid of the sword: for wrath bringeth the punishments of the sword, that ye may know there is a judgment.
I see this as the sword of God's judgment. We have read that those who live by the sword, shall die by the sword.
Mat 26:52 Then said Jesus unto him, Put up again thy sword into his place: for all they that take the sword shall perish with the sword.
What we should fear is the wrath of God or the judgment of God against evil doers. To fear God is a just and righteous act. To take up the sword, to use force to achieve an ungodly purpose is setting yourself up for the judgment of God. It may not be directly from God, as a fire from heaven, as in the final war against God, but those who sin are actually warring against God. They may die by the sword of their enemy as a just punishment. Or they may cry to God for mercy as David did after his transgression with Bathsheba.
Psa 51:2 Wash me throughly from mine iniquity, and cleanse me from my sin.
Psa 51:3 For I acknowledge my transgressions: and my sin is ever before me.
Psa 51:4 Against thee, thee only, have I sinned, and done this evil in thy sight: that thou mightest be justified when thou speakest, and be clear when thou judgest.
David received mercy from the LORD but the results of his sin played out in his family. We have eight years of Obama and now it appears that his legacy will be erased by a new conservative law abiding change of government. The ten trillion dollars of additional debt still stands and it is predicted that the dollar will crash because of this heavy debt. The results of sin cannot be entirely erased. Sins have consequences.
Coming to Jesus for forgiveness of sins will cleanse you in God's eyes. The results of your sins may still affect your children or those who were affected by them. What you sow you will reap.
Gal 6:7 Be not deceived; God is not mocked: for whatsoever a man soweth, that shall he also reap.
Gal 6:8 For he that soweth to his flesh shall of the flesh reap corruption; but he that soweth to the Spirit shall of the Spirit reap life everlasting.
So seek God to do his will and receive Jesus as your savior. An eternity in the presence of a loving God is your reward. This is the undeserved grace of God. Thank you Jesus.