4:13 Jesus believed that the disciples should have understood the parable of the soils. It is, after all, one of the easier ones to understand.
"The blindness of men is so universal that even the disciples are not exempt from it."108
4:14-20 Jesus did not give His disciples several hermeneutical principles by which they could understand the parables. He gave them a sample interpretation as a pattern that they could apply in understanding other parables.
The seed represents the word or message of God that the sower proclaims. People make a negative or a positive response when they hear this message. They may make a negative response for any one of three reasons. Regardless of the reason, a negative response proves unproductive in their lives. A positive response, however, will produce spiritual fruit, but the fruit will be in varying amounts depending on various factors.
Some interpreters want to know which soils represent believers and which unbelievers. This was not Jesus' point in the parable. Both believers and unbelievers need to welcome the word gladly rather than allowing its enemies to make it unfruitful. The enemy in the first instance is Satan (v. 15). In the second it is the flesh (vv. 16-17), and in the third it is the world (vv. 18-19).
The word that Jesus was sowing was the good news concerning the coming messianic kingdom. The people He addressed gave these characteristic responses. However these are typical responses that have marked the proclamation of God's Word throughout history. Mark's original readers would have found encouragement in this parable to receive the Word of God as good soil and to beware of the enemies that limit Christians' fruitfulness.
"Words may be sound and lively enough, but it is up to each hearer to let them sink in and become fruitful. If he only hears without responding--without doing something about it and committing himself to their meaning--then the words are in danger of being lost, or of never coming to anything. The whole story thus becomes a parable about the learner's responsibility, and about the importance of learning with one's whole will and obedience, and not merely with one's head."109
