Now this parable is this: the seed is the word of God. And those beside the road are those who have heard; then the devil comes and takes away the word from their heart, so that they may not believe and be saved.
And those on the rocky soil are those who, when they hear, receive the word with joy; and these have no firm root; they believe for a while, and in time of temptation fall away.
And the seed which fell among the thorns, these are the ones who have heard, and as they go on their way they are choked with worries and riches and pleasures of this life, and bring no fruit to maturity.
And the seed in the good soil, these are the ones who have heard the word in an honest and good heart, and hold it fast, and bear fruit with perseverance
I'm thinking along these lines as well. The one unforgiveable sin is to "speak against the Holy Spirit". IOW, those that deny The Gospel will not be saved. Also, it implies everyone will be given that opportunity to accept or deny The Gospel.
If I'm right it's just one more example of how deserving we are of God's wrath in that no one can deny that the Holy Spirit called them. Does it mean there is some degree of free will involved I'm not sure. From the individual's perspective it sure seems like it, but from God's percpective I don't see how. God knows what we will do before we our born. God already knows who will answer the call and who won't.