In the same manner that Nathan used a parable to show David his sin in a way to make him admit it (2 Samuel 12:1-14), Jesus would use parables to teach the Pharisees and the scribes. When they accused Jesus of eating with sinners, He told the parables of the lost sheep, the lost coin, and the lost sons (Luke 15:1-32).
When studying the parables it is important to understand that they usually had one overall purpose. The details show that a parable was true to life. The parables mentioned in Luke 15 showed the Pharisees and the scribes that they would search for that which was lost, if it was of profit to them, but they were not concerned with those lost in sin.
In Matthew 13, there are five parables focused on the kingdom of heaven. This a term used often by Matthew. It is "of heaven" in that it is not physical and it has divine origin and rule. The kingdom parables were taught by Jesus to prepare the people for the coming of His church (Matthew 16:18; cf. Acts 2). In Matthew 16 we read of Jesus giving Peter the keys of the kingdom (Matt. 16:19) and in Acts 2 we read of the Holy Spirit descending upon the apostles, which was promised (John 16:7-15) and Peter preaching the first sermon calling people into the kingdom, also appropriately described as Jesus's church.
"Therefore let all the house of Israel know for certain that God has made Him both Lord and Christ--this Jesus whom you crucified. Now when they heard this, they were pierced to the heart, and said to Peter and the rest of the apostles, "Brethren, what shall we do?" Acts 2:36-37
Now back to Matthew 13:
1. Parable of the Mustard Seed (13:31-32)
The mustard seed was tiny, yet produced a very large shrub with wide, spreading branches. It was usually planted in a field and become a gathering place for birds. The lesson here has to do with the tremendous growth of the kingdom. It would have small beginnings (Jerusalem) and eventually spread throughout God's entire creation (Colossians 1:23).
2. Parable of Leaven (13:33-35)
Baking bread was an every day occurrence for the original hearers of this parable. The spreading influence of leaven placed in meal was well known to all. Jesus here taught that the kingdom works from within. The gospel of the kingdom changes people. Leaven is aggressive. It refuses to be discouraged. The early Christians worked as leaven for "those who were scattered went everywhere preaching the word" (Acts 8:4). This is a parable on the influence of the kingdom and how it works from within like leaven.
3. Parable of the Hidden Treasure (13:44)
I think it is fair to say that most people at some time has fantasized about discovering buried treasure. It was evidently a common practice during the time period of Jesus on earth for people to attempt to preserve their precious things by hiding them from robbers. This parable and the next one point to the value of the kingdom of heaven. In this parable, the kingdom of heaven was worth more than all the man currently owned.
4. The Pearl of Great Price (13:45-46)
This man had been searching all his life for such a pearl. It was of such value to him that, upon finding it, he sold everything to obtain it. To stand in the truth is worth more than houses, lands, riches, friends, jobs, or even relatives. This parable teaches the wisdom of giving up all we have to gain the kingdom.
5. The Parable of the Net (13:47-50)
This parable teaches that there will be gathered into Jesus's church people who will be faithful unto death and those who will not. As a fisherman sits on the shore and separates the good fish from the bad, even so, in the judgment, God will separate the faithful and the unfaithful. The unfaithful will be lost. This is a parable of judgment.
In conclusion, it is profitable for us all to consider our current state of being in this life. Am I in the kingdom? If not, what is keeping me from entering into the kingdom and gaining eternal life? Disbelief? Ignorance? Arrogance?
Jesus said, "If anyone wishes to come after Me, he must deny himself, and take up his cross daily, and follow Me. For whoever wishes to save his life will lose it, but whoever loses his life for My sake, he is the one who will save it. For what is a man profited if he gains the whole world, and loses or forfeits himself? (Luke 9:23-25)
The disciple of Jesus Christ has a faith that is built upon reasons and evidence. It is not a blind faith. If you desire to consider these reasons and evidences then begin your pursuit of the truth. Use this site. Request a Bible study. Do not let today's obligations or tomorrow's obligations or the false assurance of long life deceive you. These matters are crucial and demand urgency.