Warning: Don't Fight in Your Own Strength

John Owen warns that attempting to kill sin without the Holy Spirit is not only ineffective but spiritually dangerous. He argues that apart from the Spirit, any "mortification" is merely a false religion of self-invention.

Owen highlights several specific warnings for those who fight sin in their own strength:

* The Trap of Legalism and Hypocrisy: Without the Spirit, efforts to kill sin often become "outside worship"—changing outward behavior while leaving the heart unchanged. This leads to becoming a "self-justiciary" or a hypocrite rather than a true Christian.

* Vain and Helpless Remedies: Owen bluntly states that "all other ways of mortification are vain; all helps leave us helpless". No amount of human diligence, watchfulness, or intention can heal a soul if it is not regenerate and led by the Spirit.

* Strengthening the "Old Man": Neglecting the Spirit’s power doesn't just fail to kill sin; it can actually "rot the new man" and renew the strength of your sinful nature.

* The Danger of False Peace: Those fighting without the Spirit often "speak peace" to themselves prematurely. They may feel a temporary sense of victory based on sheer willpower, which Owen warns is a "fatal mistake" because the sin will eventually revive and prove deadly.

* Spiritual Despair and Exhaustion: Attempting to "make brick without straw" (fighting without strength) leads to a burdensome, ensnared conscience. This eventually results in pride if you succeed outwardly, or deep despair when you inevitably fail.