From Of the Mortification of Sin in Believers
. . . reasons why the papists can never, with all their endeavors, truly mortify any one sin, among others are:
Because many of the ways and means they use and insist upon for this end were never appointed of God for that purpose (i.e., rough garments, their vows, penances, disciplines, their courses of monastical life, and the like;).
Because those things that are appointed of God as means are not used by them in their due place and order – such as are praying, fasting, watching, meditation, and the like.. (59).
Why Mortification is the Work of the Spirit
He is promised of God to be given unto us to do this work.
We have all our mortification from the gift of Christ, and all the gifts of Christ are communicated to us and given us by the Spirit of Christ (60).
How the Spirit Mortifies Sin
By causing our hearts to abound in grace and the fruits that are contrary to the flesh, and the fruits thereof and principles of them.
By a real physical efficiency on the root and habit of sin, for the weakening, destroying, and taking it away.
He brings the cross of Christ into the heart of a sinner by faith, and gives us communion with Christ in his death and fellowship in his sufferings (61)
If the Spirit Alone Mortifies Sin, Why Are We Exhorted to Mortify It?
It is no otherwise the work of the Spirit but as all graces and good works which are in us are his.
He does not so work our mortification in us as not to keep it still an act of our obedience (62).
