Mortification prunes all the graces of God, and makes room for them in our hearts to grow. The life and vigour of our spiritual lives consists in the vigour and flourishing of the plants of grace in our hearts. Now, as you may see in a garden, let there be a precious herb planted, and let the ground be untilled, and weeds grow about it, perhaps it will live still, but be a poor, withering, unuseful thing. You must look and search for it, and sometimes can scarce find it; and when you do, you can scarce know it, whether it be the plant you look for or no; and suppose it be, you can make no use of it at all. When, let another of the same kind be set in the ground, naturally as barren and bad as the other, but let it be well weeded ,and every thing that is noxious and hurtful removed from it,—it flourishes and thrives; you may see it at first look into the garden, and have it for your use when you please. So it is with the graces of the Spirit that are planted in our hearts. That is true; they are still, they abide in a heart where there is some neglect of mortification; but they are ready to die, Rev. iii 2, they are withering and decaying.
The heart is like the sluggard’s field,—so overgrown with weeds that you can scarce see the good corn. Such a man may search for faith, love, and zeal, and scarce be able to find any; and if he do discover that these graces are there yet alive aud sincere, yet they are so weak, so clogged with lusts, that they are of very little use; they remain, indeed, but are ready to die. But now let the heart be cleansed by mortification, the weeds of lust constantly and daily rooted up (as they spring daily, nature being their proper soil), let room be made for grace to thrive and flourish,—how will every grace act its part, and be ready for every use and purpose!
– John Owen –
from The Mortification of Sin in Believers, volume 6 of Works, page 23