Put to death…what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry. On account of these the wrath of God is coming. In these you too once walked, when you were living in them. But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth. Do not lie to one another, seeing that you have put off the old self with its practices and have put on the new self, which is being renewed in knowledge after the image of its creator. (Colossians 3:5-10)
The heart is like a lazy man’s field, so overgrown with weeds that you can barely see the good corn. Such a man may search for faith, love, and passion, and barely be able to find any. And if he does discover these graces are there, still alive and sincere, they are so weak and so clogged with lusts that they are of very little use. They remain indeed, but they are ready to die. But now let the heart be cleansed by mortification (i.e. putting to death our sin). The weeds of lust must be constantly and daily rooted up, as they spring up daily, our nature being their proper soil. Let room be made for grace to thrive and flourish; how will then every grace act its part and be ready ready for every use and purpose? (Taken from Mortification of Sin. Read it for free here).
The point: growing up as a Christian requires both pulling the weeds of sin and nourishing the fruit of faith. You will never grow if you are not constantly pulling out and throwing away the weeds that choke out the fruit of Christ in you. As a farmer grows crops he must equally pull out the weeds. As you seek to put on Christ you must equally put off sin. To grow in our life in Christ we must kill the sins of death.
What needs to be pulled in you? How will you do it?