In his book The Mortification of Sin, John Owen, enumerates six deadly and serious symptoms that accompany a lust. “If they are deadly and serious,” Owens says, “then extraordinary remedies must be used. The ordinary course of mortification will not work.” The first symptom he lists is as follows:
1. Firm establishment over a long period of time and settlement as an habitual practice. If a sin has been corrupting your heart for a long time, and you have allowed it to prevail and abide in power, without vigorously attempting to kill it, and heal the wounds that it causes, this is a serious condition. Have you permitted worldliness and ambition to divert you from the important duties that promote communion with God for a long season? Have you allowed unclean thoughts to defile your heart with vain, foolish, and wicked imaginations for many days? This is a serious and dangerous symptom. ‘My wounds stink and fester because of my foolishness’ (Psalm 38:5). When a lust has remained a long time in the heart, corrupting, festering, and poisoning, it brings the soul into a woeful condition. In this instance an ordinary course of humiliation will not be sufficient. Such a lust will make a deep imprint on the soul. It will make its company a habit in your affections. It will grow so familiar to your mind and conscience that they are not disturbed at its presence as some strange thing. It will so take advantage in such a state that it will often exert itself without you even taking notice of it at all. Unless a serious and extraordinary course is taken, a person in this state has no grounds to expect that his latter end shall be peace. How will such a person be able to distinguish between the long abode of an un-mortified lust and the dominion of sin, which cannot happen to a regenerate person? And how can he hope that it will ever be any different with him when he sees his lust fixed and abiding for so long? It may be that great afflictions or mercies did not dislodge it, even though these gained the special attention of your soul. These lusts may have weathered many a storm and prevailed under the display of a variety of ministries of the word of God. If this is the case, do you think it will prove an easy thing to dislodge such a roommate, pleading to stay? Old and neglected wounds can prove to be fatal, and are always dangerous. Indwelling lusts grow rusty and stubborn because they have long continued in ease and quiet. Such a sin will not be easily ejected. It will never die by itself, and if it is not daily killed it will gather added strength.”
Let us call upon God for grace and help in time of need, and let us then treat besetting sin as we would someone who sought to kill and rob us.