2. There will be no mortification of any sin without sincerity and diligence in a universality of obedience.
Owen gives the example of the man who works towards mortification in one particular lust, yet neglects another sin, and he states that such a man will not conquer. Say a man struggles with lying. He simply cannot stop misleading people, embellishing his stories, or deceiving his friends. Nevertheless, he has felt convicted by the destructive consequences of his lying, and wishes for this struggle to cease. He wants to mortify the lust of lying, and this is a good aim. All the while, however, he has another struggle with gluttony. He just loves food, loves to have his stomach loaded to the brim, and he cannot stop eating until he is overcome with abundant satisfaction. Now, this gluttonous struggle he still seeks to keep to himself. He does not feel the need to mortify this lust quite yet, and so he only seeks the mortification of his lying, and not his gluttony.
This example will ring true with a lot of us. I shamefully confess that I have often found myself conducting this very scheme. We recite to God in our prayers, “Lord, give me the grace to overcome this sin.” And in the back of our minds, almost immediately, another sin in need of mortification comes to mind, and we neglect it. If we were honest, we indeed respond, “Oh, but that sin does not have the outward consequences of this other sin. No one else is really hurt by that sin.” Owen wants to make the point that mortification is not like this – i.e., a practice of isolating lusts. It is a practice of universal obedience, where every thought and action is taken captive; and there is a very important reason why this is the case, which is revealed in the principle guiding particular mortification.
Why do we isolate certain lusts, and yet resolve to leave others alone? It is principally rooted in self-love. Rather than hating sin for sin, which would stir us to pursue universal mortification, we hate only those sins that cause us discomfort. The purpose of particular mortification is selfish in nature, while universal mortification reveals a deep longing to honor God. “If you hate sin as sin, every evil way, you would be no less watchful against everything that grieves and disquiets the Spirit of God, than against that which grieves and disquiets your own soul. It is evident that you contend against sin merely because of your own trouble by it.” In the example given above, the lying glutton only sought to mortify his lying because of the discomforting consequences that had befallen him because of that sin. His gluttony was not all that discomforting to him, thus he sought not to mortify it. Therefore, it is obvious that he sought to mortify sin because of his self-love, his love for his own comfort, not because of his hatred of the sin as sin. If he had hated sin as sin, and not merely hated sin as discomforting, he would not have neglected the mortification of his gluttony.
“Hatred of sin as sin, not only as galling or disquieting, a sense of the love of Christ in the cross, lies at the bottom of all true spiritual mortification.” A true love for Christ and an honest recognition of the payment that He paid will naturally burden our hearts with a serious desire to mortify every sin, not merely because sin is a discomfort to our own prosperity or reputation among the church body, but because it dishonors the one who is our greatest treasure, our Savior and Lord.
Moreover, this isolation of lusts is to no effect in the long run. Each lust is a stream, yet indwelling sin is a fountain. If we extend all our efforts at blockading the stream, the fountain simply alters its course; it does not surrender its power, only its manifestation. Let us seek universal holiness for the sake of living in a manner worthy of the gospel, because we hate sin as sin, and seek to honor our Father in heaven.
 John Owen, Overcoming Sin and Temptation, ed. Kelly M. Kapic and Justin Taylor (Wheaton, IL: Crossway, 2006), 87.
 Ibid., 87.