The blood of Jesus

1 John 1:7King James Version 

But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin

Are you washed in the blood of Jesus Christ?

And almost all things are by the law purged with blood; and without shedding of blood there is no remission of sins.
The devil and his demons hate this song, so sing it as often as you can with all your heart. This is our weapon against the enemy.
The best songs for worship of God are the old songs and those with the bible verses.