As with a bonsai tree, small roots and branches stunt growth. What kind of soil are we, since God sows the Word in us? The seed is always good, so any fault lies with the soil. If our hearts are hard, the Word bounces off our entrenched ignorance that rejects it from the beginning. If our hearts are rocky and shallow, the Word can start growing but cannot continue because it has not deepened. The world tries to make us shallow and so open-minded that the Word falls out - it's "un-Christian" to stand dogmatically on the unaltered, error-free Word.
If our hearts are thorny, the thorns peck at us, with worldly cares illogically choking off our faith. Other pleasures invade the weekends set aside for us to worship God. Shockingly, we are all each soil, each bad in its own way! "Who will save me from this body of death?"
Jesus Christ. There is no excuse not to improve the soil - since it is not we who improve it. Our efforts are putrid to God. Step 1 is to realize this. Step 2 entails God using the Word and Sacraments constantly to work on this. The Law conditions the soil by thoroughly shredding it. Then Gospel, the seed, is sown, and we are watered. This is via daily contact with the means of grace - God does it. We go by what He says, not fitting it to our expectations. Works come naturally from this work. He will grow it.
Soli Deo gloria.