Clarifying some of the allusions here:
Stagger Lee is a man who got in a drunken fight with another man and when the man took his hat Stagger Lee shot him. It is a nickname used for the man and popularized in a blues song by Mississippi John Hurt.
Old Scratch is another name for the Devil.
The song overall seems to be Clutch saying how much they are tight with God.
Clarifying some of the allusions here: Stagger Lee is a man who got in a drunken fight with another man and when the man took his hat Stagger Lee shot him. It is a nickname used for the man and popularized in a blues song by Mississippi John Hurt.
Old Scratch is another name for the Devil.
The song overall seems to be Clutch saying how much they are tight with God.