Book Review: Of the Mortification of Sin in Believers

For if you live according to the flesh you will die, but if by the Spirit you put to death the deeds of the body, you will live. - Romans 8:13

John Owen was a prolific Puritan author in the 1600's, producing over the course of his life a library of works that fill over 15 volumes. But out of all his writing, there is one that has risen to the top again and again, instructing new generations of Christians on the bloody subject of sin-killing. Even today this work remains just as needed and insightful as ever. Its full title for the 1656 publication was "Of the Mortification of Sin in Believers: The Necessity, Nature, and Means of it. With a resolution of sundry cases of conscience, thereunto belonging"

Of the Mortification of Sin in Believers is being highlighted here on The Relentless Fight because it is a classic text on WHY to kill sin, and HOW to kill sin. The book is a short treatise, roughly 100 pages, based on an exposition and meditation of Romans 8:13 which reads, "For if you live according to the flesh you will die, but if by the Spirit you put to death the deeds of the body, you will live."  In the language of 1656, to "mortify" meant to put to death. Therefore "mortification of sin" was the killing of sin.

Justin Taylor summarizes the structure of the book in the edited compilation of 3 of Owen's works called Overcoming Sin & Temptation. He identifies 3 parts:

1. The Necessity of Mortification: believers must make it their daily work to mortify the fleshly sin in them, the Spirit is required for this work, and the life of the believer depends upon this work. 
2. The Nature of Mortification: What it is NOT (i.e. the utter destruction of sin, or an occasional victory, or a surface-level change), but rather, "mortification consists in a habitual weakening of sin" which involves relentless fighting. He then offers 9 practical considerations. 
3. The Means of Mortification: We set our faith on the work of Christ (in the cross), and we rely on the power of the Holy Spirit to accomplish the killing of sin. 

Here are a few highlights, quotes, and applications:

• Mortification is by God's grace: We cannot successfully fight sin without God's help. "Mortification from a self-strength, carried on by ways of self-invention, unto the end of a self-righteousness, is the soul and substance of all false religion in the world." page 47 and "The use of means for the obtaining of peace is ours; the bestowing of it is God's prerogative." p 64 also "Mortification of any sin must be by a supply of grace. Of ourselves we cannot do it." p 133
• Mortification is only for believers, and by the Spirit: Speaking of unbelievers, "Let men know it is their duty, but in its proper place; I take not men from mortification, but put them upon conversion. He that shall call a man from mending a hole in the wall of his house, to quench a fire that is consuming the whole building, is not his enemy. Poor soul! It is not your sore finger but your hectic fever that you are to apply yourself to the consideration of. You set yourself against a particular sin and do not consider that you are nothing but sin." p 84 and of the need for the Holy Spirit, "This whole work, which I have described as our duty, is effected, carried on, and accomplished by the power of the Spirit, in all the parts and degrees of it" p 138
• Remember the Gospel!: "Act faith peculiarly upon the death, blood, and cross of Christ; that is, on Christ as crucified and slain. Mortification of sin is peculiarly from the death of Christ." p 136 and again "Set faith at work on Christ for the killing of your sin. His blood is the great sovereign remedy for sin-sick souls. Live in this, and you will die a conqueror; yea, you will, through the good providence of God, live to see your lust dead at your feet." p 131
• Be exceedingly violent against your sin: "Such a one never thinks his lust dead because it is quiet, but labors still to give it new wounds, new blows every day." p 77 At first temptation, "Rise up with all your strength against it, with no less indignation than if it had fully accomplished what it aims at." p 110
• The fight against sin must be relentless: Never take a day off against sin. Always fight it. "Do you mortify; do you make it your daily work; be always at it while you live; cease not a day from this work; be killing sin or it will be killing you." p 50 and "...know there is no safety against it but in a constant warfare." p 52 and "As it never dies of itself, so if it be not daily killed it will always gather strength" p 91
• It's a hard long fight: Mortification is not the utter killing of sin. We aim for it, but in this life we will not accomplish it. Rather, mortification is "a habitual weakening of sin". We crucify the flesh, and it is bleeding out. (For more on this expectation, see the TRF post Expect a Hard Long Bloody Fight)
• Sometimes God allows sin as a fatherly discipline: "How do you know but that God has suffered the lust wherewith you have been perplexed to get strength in you, and power over you, to chasten you for your other negligences and common lukewarmness in walking before him; at least to awaken you to the consideration of your ways, that you may make a thorough work and change in your course of walking with him?" p 88

If you would like a more eloquent summary of the book, please read this excellent brief article by Jen Pollock Michel called The Bloody Business of Killing Sin, on The Gospel Coalition website.

You can buy the book on Kindle for only $0.99, or as an abridged paperback from Banner of Truth for only $8.10. But perhaps the best version is a 3-part John Owen collection (edited, with footnotes) called Overcoming Sin & Temptation. All page numbers in this post have been referenced to this edition, which includes not only Of the Mortification of Sin in Believers, but also the two Owen books: Of Temptation, and Indwelling Sin.

Always killing sin,
The Relentless Fight