Plant some seeds and see what happens.
And he said, So is the kingdom of God, as if a man should cast seed into the ground; And should sleep, and rise night and day, and the seed should spring and grow up, he knoweth not how. For the earth bringeth forth fruit of herself; first the blade, then the ear, after that the full corn in the ear. But when the fruit is brought forth, immediately he putteth in the sickle, because the harvest is come. (Mar 4:26-29)
Much of the teaching of Jesus was done through parables, a short story or analogy that describes a spiritual principle. Teaching this way has many advantages, one of which is that we learn best by relating what we don't know to the things we do know. To a people involved in farming, parables of planting, growing and harvesting use ideas familiar to the listeners. If you have ever planted a garden you know that just looking at the seed and soil doesn't tell you how much you will be able to harvest. Certainly, a good gardener gets a feel for the soil, knows how to test it and improve it. But when you look at the seed and the soil it is not possible to tell right away if the seed will germinate and grow and how much fruit it will produce. You have to plant the seed and wait.
Teaching spiritual things is like this, Jesus says. You plant the seed (the knowledge of the Gospel) and then wait. If the soil is good the seed will eventually grow and bear fruit. The gardener mostly just waits for that to happen. True, he must insure the seed gets the water it needs and he must remove any weeds that spring up to compete with his seeds. Yet, the gardener doesn't really make the seeds grow. It is the nature of the seed and the soil to produce growth.
The meaning in this parable of Jesus is fairly obvious. Planting the seed refers to preaching the Gospel and teaching the knowledge of God's ways to people. The soil refers to the person who receives that teaching. In order for the knowledge to develop into a spiritual life, the seed must be good and the soil must be good.
First, we must make sure we preach and teach the true message that God has revealed to man. This involves our own level of understanding and our ability to express that understanding. We must study and learn so that we understand the message and know that we have the right message. It isn't enough to just read the Bible to gain that knowledge. What is really required is that we live it. If we see our knowledge bear fruit in our own life, then we know for certain that we have the right message. It's all well and good to make a detailed exegesis of the Bible, but it is so much better to be able to say, "And it really is that way because that is what happened to me." We want to be able to say honestly, "Try it - it works." Thus when we preach and teach on the words of Jesus, we don't have to sound like some seminary trained expert. We simply have to relate how the knowledge of God changed our lives. Like this:
And he said unto them, Take heed what ye hear: with what measure ye mete, it shall be measured to you: and unto you that hear shall more be given. For he that hath, to him shall be given: and he that hath not, from him shall be taken even that which he hath. (Mar 4:24-25)
These verses came immediately before the parable about planting the seed. The promise that Jesus gave to his disciples was that if they pay attention to his teaching, put it into practice, live by it, then they would receive even greater understanding. If the words of Jesus are not practiced every day, the knowledge slips away. If we don't apply the knowledge to our lives, nothing will come of it and even that knowledge we do have will be lost. Even more so, if we take that knowledge and spread it to others, even more will be given to us.
The second part of this parable has to do with the soil. There is always the temptation to try and figure out where the good soil is. In other words, we want to prejudge the listener to determine if they are "one of us." That is not the way we are to do it. Remember that until the seed is planted and nurtured we won't know if the soil is good. In the same way that we know we have the right message by living it, we find the lost by giving them that message and watching to see what happens. Just as the gardener must wait for the seed to grow, we must wait and watch to see how the message changes the listener's life. This may take time and we must be patient. And we always remember that it is the mysterious working of the unseen force of the Holy Spirit that causes the seed of knowledge to germinate, grow and bear fruit in that person's life. Our obligation is to plant the seed and water the soil. We preach the message and give encouragement and support to those that receive it.
What goes along with this is that we don't reject people out of hand just because they are not what we expect a good Christian to be. Jesus said that the physician comes to heal the sick, not the healthy. Likewise, if we are engaged in teaching, there isn't much point it teaching to those who already know. That type of self-serving activity may make us feel good about ourselves but doesn't do the work of the Kingdom of God. The work of the gardener is to create new life where there is none, or to nurture growth where the seed has been planted. The soil is empty to begin with and only later does it create a harvest.