“they may indeed see but not perceive,
and may indeed hear but not understand,
lest they should turn and be forgiven.”
 And he said to them, “Do you not understand this parable? How then will you understand all the parables?  The sower sows the word.  And these are the ones along the path, where the word is sown: when they hear, Satan immediately comes and takes away the word that is sown in them.  And these are the ones sown on rocky ground: the ones who, when they hear the word, immediately receive it with joy.  And they have no root in themselves, but endure for a while; then, when tribulation or persecution arises on account of the word, immediately they fall away.  And others are the ones sown among thorns. They are those who hear the word,  but the cares of the world and the deceitfulness of riches and the desires for other things enter in and choke the word, and it proves unfruitful.  But those that were sown on the good soil are the ones who hear the word and accept it and bear fruit, thirtyfold and sixtyfold and a hundredfold.”
(Mark 4:10-20 ESV)
They gathered around him asking him to further explain the stories he had been telling the crowd. He told them "To you has been given the secret of the kingdom of God" and then asked the "Do you not understand this parable?".
The sower is one who sow the word of the Lord. Commentary.
1. Path listeners : those that hear the word, but Satan comes along and immediately takes it from them.
2. Rocky ground listeners:the ones who, when they hear the word, immediately receive it with joy. BUT since they aren't firmly rooted, they live for a while but when difficulties come along they fall away.
3. Thorn Listeners: They are those who hear the word, but everything else in the world is more important. So they fall away. Choked out by the cares and concerns for the world at large.
4. Good Soil Listeners: the ones who hear the word and accept it and bear fruit, thirtyfold and sixtyfold and a hundredfold. Those folks that you know love the Lord God. :)
We are also told though that for those on the outside everything is in parables so they may see but not understand what they are seeing, they may hear but not understand what they are hearing in case they might turn and be forgiven.
Have to admit, that doesn't make a lot of sense to me. Wouldn't God want people to understand what he was talking about in order to bring about repentance? So I went to the commentaries to gain some understanding.
1. Jesus wants us to know what a privilege it is for us to be called his own. We know the secret of the Kingdom of God.
2. Those outside aren't privy to that secret. Consider this. Families know how they operate, children growing up in their own families understand this intuitively, but those looking in can't "get it". So to it is with with the family of God..
3. Jesus when he taught directly was met with scorn and hatred. Not so when he taught with stories.
4. The secret of the kingdom of God isn't a secret in the North American sense (as in something to not talk about), but a secret in that it is something believers understand and others need to be drawn into understand.