Introduction to John Owen's Treatise on Indwelling Sin

The Christian cannot be stationary. He must either be in an advancing career of holiness, or in a retrograde process of backsliding. To those who have either slackened their progress, or are falling from their steadfastness, this treatise may prove a faithful monitor to apprize them of their danger. It forcibly reminds them
that they are in the enemies' country — that the Christian life is a state of incessant warfare.