This corruption of nature, during this life, doth remain in those that are regenerated:l and although it be through Christ pardoned and mortified, yet both itself, and all the motions thereof, are truly and properly sin. Every sin, both original and actual, being a transgression of the righteous law of God, and contrary thereunto, does in its own nature, bring guilt upon the sinner, whereby he is bound over to the wrath of God, and curse of the law, and so made subject to death, with all miseries spiritual,temporal, and eternal. WCF 6.5-6.6
"God sees it best for us that we should be complete in nothing in ourselves, that in all things we must be 'complete in Christ,' which is best for us (Col. 2:10)" (Overcoming Sin and Temptation)
Resources
Indwelling Sin by C. H. Spurgeon
Indwelling Sin Pulls Down the Plumes of Remaining Pride! by Thomas Watson
Why Does God Allow Sin to Remain in the Regenerate? by Thomas Boston
Indwelling Sin and the Believer by John Newton
Indwelling Sin, Positional Sanctification, and Progressive Sanctification by Dave Jenkins
Only a Christian Can Mortify Sin by Horatius Bonar
The Christian's Warfare by Robert Murray McCheyne
How to Mortify Sin by Sinclair Ferguson
More Resources on Mortification
eBooks
The Remainders of Indwelling Sin in Believers (eBook) by John Owen
A Treatise of the Dominion of Sin and Grace by John Owen
The Sinfulness of Sin (eBook) by Ralph Venning
The Sins of Saints (eBook) by A. W. Pink
Mortification of Sin in Believers (eBook) by John Owen
Sin's Overthrow: A Godly and Learned Treatise of Mortification (eBook) by John Preston
The Mortified Christian by Christopher Love
The Spiritual Warfare by Andrew Grey
The Christian Warfare by John Downame
The Holy War by John Bunyan
The Whole Armor of God by William Gouge
The Doctrine of Sanctification by Charles Hodge
The Christian Warrior: Wrestling with Sin, Satan, the World and the Flesh by Isaac Ambrose
The Trial of a Christian's Growth by Thomas Goodwin
The Method of Grace by John Flavel
Multimedia
Romans 8:1-11 - Free from Indwelling Sin by R. C. Sproul
Of the Fall of Man, of Sin and of Punishment (Ch.6, Sec.6) by Greg Bahnsen
Fighting Against Indwelling Sin (MP3) by Joel Beeke
The Problem of Indwelling Sin (MP3) by Curt Daniel
Reason to Mortify Indwelling Sin (MP3) by Cornelis Pronk
Indwelling Sin (MP3) by Charles R. Biggs
Killing Remaining Sin (MP3) by Joel Beeke
Christians Engaged with In Warfare With Remaining Sin 1 (MP3) by Al Martin
Christians Engaged with In Warfare With Remaining Sin 2 (MP3) by Al Martin
Christians Engaged with In Warfare With Remaining Sin 3 (MP3) by Al Martin
Christians Engaged with In Warfare With Remaining Sin 4 (MP3) by Al Martin
Putting to Death Remaining Sin (MP3) by Geoff Thomas
Reigning Righteousness & Remaining Sin (MP3) by Greg Nichols