In his little book Of Temptation, in a section on “deceitful assistances” in fighting against sin, ODG John Owen warns about
The most vigorous actings, by prayer, fasting, and other such means, against that particular lust , corruption, temptation, wherewith you are exercised and have to do. This will not avail you if, in the meantime, there be neglects on other accounts. To hear a man wrestle, cry, contend as to any particular of temptation, and immediately fall into worldly ways, worldly compliances, looseness, and negligence in other things, — it is righteous with Jesus Christ to leave such a one to the hour of temptation (John Owen, Of Temptation (Joseph Kreifels), pp. 147-48).
It is overwhelming, to me at least, to think of fighting all sin at once. It is too easy to let the “little sins,” or some private sins, go unchallenged while we focus on the “biggies.”
Owen says that to do such is a deceitful assistance, to imagine that we can address sin on one part of our lives while neglecting the sin in other parts.
Perhaps Owen is given to some hyperbole here, but his point should be given careful consideration. Sin is not an all or nothing proposition. It will take whatever it can get from us.