Secondly, we should note that there are no shortcuts to spiritual growth. Any farmer will tell you that you can’t “pray over” trees and thereby circumvent the laws of nature and cause them to bear fruit overnight.
Regarding the subject of Mortification, three things must be noted: (1) We need it, (2) The type of things that need mortifying, (3) The facts of our case.
It is a simple fact that in the Lord’s children there are many remaining vestiges of our fallen nature, corrupt frames of mind and wicked desires. These must be rejected and fought against with the most fervent abhorrence and loathing. Whole books have been written on this subject. John Owen's The Mortification of Sin in Believers comes to mind. It is, as I have already said, a simple fact that in the Lord's children there remains indwelling corruptions that must be battled with. The Lord’s children are too ready to hold these corruptions tightly, as if they were dear friends. Our regeneration and former progress in mortification should not make us indulgent, but rather more vigilant. We must be on constant guard, zealous to work out what God has worked in.
The primary evidence any of us has that we are, in fact, regenerate, is our battle and victory over the sin that still infects our humanity. In other words, a person who never senses a struggle between the flesh and Spirit, and never experiences any kind of victorious growth in holiness, has no reason to assume that he is regenerate.
Our text lists several sins - certainly not a comprehensive catalogue - that a child of God is likely to find within his own heart and therefore must be prepared to mortify.
1. Malice. This may be defined as delighting in another’s hurt. Not only is the actual hurting of our neighbor an evil, but the very intent of the heart to do him wrong is an evil that needs to be mortified. Matthew Henry says, "Malice is anger resting in the bosom of fools, settled overgrown anger, retained till it inflames a man to design mischief, to do mischief, or delight in any mischief that befalls another."
2. Guile. This is deception or exploitation. We must always remember that the Lord takes notice of our cunning conniving and schemes.
3. Hypocrisy. We can define this as presenting a false image of oneself. All forms of hypocrisy are detestable to God, not simply religious hypocrisy.
4. Envy. This is best described as pouting at another's good. Galatian 5:21 affirms that this is an attitude common to all. To be grieved and vexed at another’s good is detestable to God and injurious to self.
5. Evil Speaking. This would be defamation of another’s character. Someone has said that speaking evil of others is the fruit that grows upon malice, envy and other internal evils and is betrayed to be prevalent in our hearts by the existence of evil speaking.
There may be ONE sin to which the heart of a regenerate individual is especially prone. We are all perhaps aware of this truth. When seem to come back to the same issue over and over again in our lives, might this not be our 'besetting sin'?
There are degrees of strength of unmortified corruptions and many ways they vent themselves. Notice that our text says "all." The word, “all,” means that one branch may be cut off but leave many others untouched. If we examine our lives carefully, we will likely see things that are the root causes of our lapses in Christian character. If we only address the outworking branches, leaving the root untouched, we will continue to deal with this same thing. The correct way to mortify sins is to begin with the inward roots that are in the heart. An ounce of prevention is worth a pound of cure.
The last clause of verse 2 (that ye may grow thereby), is asserting that we are not receiving the Word in a way that causes our souls to grow until we first set about the work of mortifying and putting off what the Puritans called, "the unclean frames of spirit" listed here.
This is not legalism. Our mortifying of these deeds of the flesh is nothing more that working out what God has worked in. This is not salvation by works. This is faith showing its genuineness by living in obedience to God and humbling oneself under the sanctifying work of the Holy Spirit.