Matthew 13:18 says, Hear ye therefore the parable of the sower.  In the next few verses, Jesus explains the parable of the shower.  I believe that He did this because those around Him did not hear by faith and understand on their own.  I also believe that anytime we are having trouble understanding what God is saying to us, if we only listen, the Holy Spireit will teach us the truth.  If we will really listen, then God will always make His truth known to us.  Verse nineteen states, When any one heareth the word of the kingdom, and understandeth it not, then cometh the wicked one, and catcheth away that which was sown in his heart. This is he which received seed by the way side.  Jesus tells us that anyone who hears the gospel, but allows it to simply blow over them like so many empty words, are like the seed sow by the wayside.  The wicked one, or the Devil, will be quick to snatch the truth of the gospel away from them, never even giving it a chance to take root.  Verse twenty says, But he that received the seed into stony places, the same is he that heareth the word, and anon with joy receiveth it;  Then in verse twenty-one continues, Yet hath he not root in himself, but dureth for a while: for when tribulation or persecution ariseth because of the word, by and by he is offended.  Jesus tells us that those who hear the gospel, but only accept it when things are going well, are like the seed that fell on rocky ground.  As soon as adversity comes, they turn away from the gospel, and it withers and dies for them, because it never took root in their lives.  They may have professed to believe, but it was for material reasons and not for spiritual ones.  Verse twenty-two states, He also that received seed among the thorns is he that heareth the word; and the care of this world, and the deceitfulness of riches, choke the word, and he becometh unfruitful.  Jesus said that those who hear the word among thorns are those that allow the care of the world and the deceitfulness of riches to choke the word of God and they become unfruitful.  I am not sure if we can say these people were not saved, since evidently the gospel took root, but if they were, they still allowed the things of the world to have too much importance in their lives and ceased to bear fruit for God.  Verse twenty-three says, But he that received seed into the good ground is he that heareth the word, and understandeth it; which also beareth fruit, and bringeth forth, some an hundredfold, some sixty, some thirty.  This is what we want to be as followers of Christ.  We hear and understand God's word, especially His message of salvation, and we bear fruit for Him.  Not all will bear the same amount of fruit, but all will bear fruit.