The parable of the sower is one of those interesting parables which you don't have to work too hard to interpret. Why, you may ask? Because unlike a lot of other parables, the interpretation is in the text. It's one of those passages where the meaning isn't up to a whole lot of quibbling. The text tells you what the text is about.
So why do we act as though the text is complicated?
We do this because we do not wish for the text to mean what it says. This is part of what it means when Jesus says 'anyone who will not receive the kingdom of God like a little child will never enter it.' As children, when God forbids, we fearfully consider the consequences of breaking his word. When God commands, we consider what he prompts us to do, and try to act accordingly. And when God tells you what his parables mean, children tend to take that meaning as it is printed. But eventually you grow up, you put childish things away, and you begin to look at the scriptures in a new light.
And what you find yourself doing is being too smart for the scriptures to mean what they say. You do the thing where you say 'oh gosh. Jesus Can't POSSIBLY have meant that.' You reasons for doing so are rarely because you've gotten deep into the text. Your reasons are almost always that Jesus tells you not to do what you want to do, and therefore you have a choice. Change what you do, or try to change what Jesus says. As children, we are encouraged to change our behavior. As adults, we tend to change what Jesus said. That's the automatic response.
So when it comes to the parable of the sower, it clearly says that some of the ground is inhospitable to the seed that is scattered. Some of the ground is too trodden down, or full of weeds, or rocky or what have you. Jesus bothers to explain why that is, what those various things mean, but it seems strange for us to say that all this ground is clearly hospitable to germination. It isn't.
It's very difficult to be universalist when considering this readings, given that some of the soil just isn't conducive for the growth of the seed that is scattered. Jesus clearly says that there are people, that there is soil, that will not be up for the word of God to take root and grow. You can wish that wasn't true, and I wish it wasn't true either. But that doesn't stop it from being there.
So what to do? I'm not prepared to surrender the point, given that I know that "God desires all men to be saved and to come to a knowledge of the truth." If that's the case, then what do we do with the unfertile ground?
Think about any field you've ever seen, either one that is filled with crops and is being fruitful, or one that is lying fallow for a while. Think of your garden outside of your house, or even something as simple as a window box. Think of it, and ask yourself how maintenance free it actually is. Is that space something that can be left completely alone? Or is it something that requires work? And even more than that, is work that has to be done on that garden plot something that you do once only, or do you have to do it multiple times?
If you weed your garden plot, you don't just weed it once ever. And you can't respond to criticisms of weeds being in your plot by saying 'I weeded it last year!' Weeds come back. New stones get revealed. The quality of the soil ebbs and flows, but cannot be left to its own devices. Bad soil must be improved. Good soil must be maintained.
Anyone who would read the parable and say that it is unfair, given how there seems to be some soil that is good and some bad, seems to forget that Christ is not just an arbiter of right and wrong. His primary work is not judge, but redeemer, and sanctifier. It's not as though he arrives on the earth as he who scatters the word then leaves the soil to its own devices. He's not just the sower. He's the gardener too.
We see in another parable how there is a question about a tree that is not bearing any fruit. The request from the landowner is to chop it down - why should it use up the ground? But the gardener doesn't spring into action and chop the tree down, no no. Instead, he says 'let's tend it, let's water it, let's fertilize it, and give it another year.'
In the divine service, part of what happens is that we confess, and are forgiven. And we're confessing our cares, our worries, our lack of depth or seriousness, that kind of thing. And Christ forgives. He makes new. He breaks up the path, picks the rocks, pulls the weeds, all that sort of thing. You're not good soil based on you hearing the word, you are made and kept as good soil by the work of Christ. That's his work, friends, that's what he does. To scatter the seed, and tend the soil. Sure, it goes bad, goes fallow, but that's why we go back and confess over and over again. To be restored.