The illustration of the sower and the seeds

The illustration of the wheat and the weeds concludes with a harvest in which the wheat and the weeds can be clearly told apart and separated. The weeds symbolize our inauthentic self. When we reach a certain point in our lives we are in a position to root out the weeds and harvest the authentic aspect of our lives. The question is, when does this opportunity for change - this "harvest" - present itself?

As an answer, Jesus uses another illustration:
"A sower went out to sow. And as he sowed, some seeds fell along the path, and the birds came and devoured them. Other seeds fell on rocky ground, where they had not much soil, and immediately they sprang up, since they had no depth of soil, but when the sun rose they were scorched; and since they had no root they withered away. Other seeds fell upon thorns, and the thorns grew up and choked them. Other seeds fell on good soil and brought forth grain, some a hundredfold, some sixty, some thirty."
(Matthew 13:3-8)
By way of explanation, Jesus says,
"When any one hears the word of the kingdom and does not understand it, the evil one comes and snatches away what is sown in his heart; this is what was sown along the path.

As for what was sown on rocky ground, this is he who hears the word and immediately receives it with joy; yet he has no root in himself, but endures for a while, and when tribulation or persecution arises on account of the word, immediately he falls away.

As for what was sown among thorns, this is he who hears the word, but the cares of the world and the delight in riches choke the word, and it proves unfruitful.

As for what was sown on good soil, this is he who hears the word and understands it; he indeed bears fruit, and yields, in one case a hundredfold, in another sixty, and in another thirty."
(Matthew 13:19-23)
Opportunities for change are liberally scattered like seed throughout our lives. In Romans 5:17, 21, Paul talks about the abundance of God's grace, and allowing it to reign in our lives. Favourable circumstances are everywhere, we just need to register them.

M. Scott Peck addresses this matter in The Road Less Travelled. He talks about serendipity - defined as "the gift of finding valuable things not sought for" - and connects it with the liberal availability of the grace of God.
"One of the reasons we fail to take full advantage of grace is that we are not fully aware of its presence - that is, we don't find valuable things not sought for, because we fail to appreciate the value of the gift when it is given us. In other words, serendipitous events occur to all of us, but frequently we fail to recognise their serendipitous nature; we consider such events quite unremarkable, and consequently we fail to take full advantage of them."
Opportunities are all around us. It could be something we read in a book, a newspaper, or magazine article. We might see something in a film or TV programme. Perhaps a comment from a friend, or even a stranger. Any of a multitude of things might ignite in us some small spark of self-appraisal. It is how we respond to those opportunities that matters. We might well go through much of life oblivious to the way our past influences our present, but our own bodies, or our dreams, or people around us, could well be trying to tell us something different.

Alongside this is the fact that change is not easy. It is easier to ignore the opportunity for change than it is to act on it. Jesus illustration implies that a greater percentage will do whatever they can to avoid changes in their lives.

"This is what was sown along the path"
For many, opportunities for change are missed simply because life is so hectic. Like thousands on the footpaths and sidewalks, we have our heads down, stolidly powering through the day's schedule. Today's public pavements are tarmacked hard, as if to illustrate the tough shell people have constructed to shield themselves. It would take a pneumatic drill to break through - industrial-sized effort.

If there is any awareness that things are getting crazy, we tell ourselves we are too busy to change. We never give ourselves time to stop and think, to allow a seed of change to germinate. Many have become hard-hearted. We tell ourselves that in our line of work we can't afford to be soft-hearted. We convince ourselves it is for the greater good. We do this because we don't know ourselves. What really drives us resides in the dark corners of our hearts, in places we are afraid to look.

"As for what was sown on rocky ground"
Some like the idea of change. They can see how much better their lives would be, how much happier they could be. But, once they begin trying to put these changes into action, their efforts can be sabotaged. It might be that other family members don't want to hear about your struggles with your upbringing. It could call into question their own. As you try to explain that it is not about fault or blame, your words catch in your throat. Blank expressions, or looks of horror, are enough to dry up any moisture, and the shallow roots of change wither up and die.

Or, we could be faced with the fear of religious persecution. It seems this was a real concern in the first century. John chapter 9 tells the story of the man born blind who ends up being cast out of the synagogue because he defends the man who healed him. His parents don't want to risk speaking out for fear of receiving the same punishment. But, it wasn't just the common man: John 12:42 reports that "many even of the authorities believed in him, but for fear of the Pharisees they did not confess it, lest they should be put out of the synagogue." Later, Jesus warned that this was the likely fate of any who acted on what he said.
They will put you out of the synagogues; indeed, the hour is coming when whoever kills you will think he is offering service to God. And they will do this because they have not known the Father, nor me.
(John 16:2, 3)
Things are no different today. Making changes in our lives might draw the attention of our religious community. If our beliefs change, we could find ourselves shunned by those around us. Eventually it could lead to being cast out of the community, and being cut off from friends and family. This could be too high a price to pay for some, and any joy they initially experienced is drained away.

"As for what was sown among thorns"
For many, opportunities to change can be crowded out by anxieties over day-to-day living, making ends meet, and worrying about where the next penny is coming from. We think that if we only had enough money, our problems would be over. Such is the deceptive power of riches. Even the wealthy are not free of problems.

Jesus was aware of this struggle. He implored, "Seek first his kingdom and his righteousness, and all these things shall be yours as well." In other words, if we make it a priority to change our own lives from the inside out, it will completely alter our world-view, and our attitude towards the life we have. The work we have will not seem so soul-destroying, or we realise we have the confidence to find something better.

This failure of so many to grasp the opportunities for change is what is meant by Jesus' words, "Many are called, but few are chosen." In other words, "Many are the opportunities, but few choose to take advantage of them." On the other hand, he is also recorded as saying, "if you have faith as a grain of mustard seed, you will say to this mountain, 'Move from here to there,' and it will move; and nothing will be impossible to you." If there is in us any "will to grow" (as M. Scott Peck calls it), no matter how small, it could be enough to lead to a harvest.

Ultimately, why the seed should fall where it does, and then germinate, and then go on to bear fruit, remains a mystery. It cannot be forced, and it can hardly be monitored. Even Jesus did not know how it happened. "The wind blows where it wills, and you hear the sound of it, but you do not know whence it comes or whither it goes; so it is with every one who is born of the Spirit." The record of the illustration of the sower and the seeds in Mark's account has Jesus following it up with these words:
"The kingdom of God is as if a man should scatter seed upon the ground, and should sleep and rise night and day, and the seed should sprout and grow, he knows not how. The earth produces of itself, first the blade, then the ear, then the full grain in the ear. But when the grain is ripe, at once he puts in the sickle, because the harvest has come."
(Mark 4:26-29)
If we call it a blessing, or election, we must ask, "Why?" The answer can only be a shrug. So, for the time being, if I am asked, "Why do you believe in God?" I can only answer, "I don't know. Just lucky, I guess."

Further Reading
The Road Less Travelled - M. Scott Peck