Parable of the Barren Fig Tree: Luke 13:6-9
Jesus tells the parable of the barren fig tree to vividly illustrate his warning that "unless you repent, you will all perish as they did." (Luke 13:5)
There are several important truths that this parable communicates about God, his patience, and what repentance really means.
In context, the reason Jesus tells this parable of the barren fig tree is because "At that very time there were some present who told him about the Galileans whose blood Pilate had mingled with their sacrifices." (Luke 13:1)
Apparently these people were wanting to know if this had happened to these Galileans because they had sinned. Jesus then asks them, "Do you think that because these Galileans suffered in this way they were worse sinners than all other Galileans?" (Luke 13:2)
Jesus also says, "Or those eighteen who were killed when the tower of Siloam fell on them - do you think that they were worse offenders than all the others living in Jerusalem?" (Luke 13:4)
After asking each question, Jesus responds with, "No, I tell you; but unless you repent, you will all perish just as they did." (Luke 13:5; also verse 3)
To further explain his warning, Jesus tells them this parable of the barren fig tree.
Jesus says, "A man had a fig tree planted in his vineyard; and he came looking for fruit on it and found none." (Luke 13:6)
The man goes to the gardener and says, "'See here! For three years I have come looking for fruit on this fig tree, and still I find none. Cut it down! Why should it be wasting the soil?'" (Luke 13:7)
The gardener replies, "'Sir, let it alone for one more year, until I dig around it and put manure on it. If it bears fruit next year, well and good; but if not, you can cut it down.'" (Luke 13:8-9)
Jesus does not restate his point at the end of this parable of the barren fig tree, because he has already made his point before telling the parable. He is telling this parable to emphasize that unless we repent and "bear fruits worthy of repentance" (Luke 3:8), we will perish.
The barren fig tree represents the people of the world; and its being "barren" represents sin.
This idea of the fig tree being barren, and the fact that it is expected to produce fruit, reinforces the idea of repentance being a complete change in actions and thoughts (by no longer sinning).
In this story, the barren fig tree is allowed to have more time to live, so it can have the opportunity to produce fruit. However, if the fig tree continues to not produce fruit, eventually it will be cut down. As Jesus says, "Every tree that does not bear good fruit is cut down and thrown into the fire." (Matthew 7:19)
Essentially, we are fig trees, and if we remain barren by sinning then we will be cut down.
As Paul says regarding repentance, "Do you not realize that God's kindness is meant to lead you to repentance?" (Romans 2:4) Paul also says, "Do you not know that wrongdoers will not inherit the kingdom of God? Do not be deceived! Fornicators, idolaters, adulterers, male prostitutes, sodomites, thieves, the greedy, drunkards, revilers, robbers—none of these will inherit the kingdom of God." (1 Corinthians 6:9-10)
The author of Hebrews also warns of the importance of repentance, saying, "For if we willfully persist in sin after having received the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful prospect of judgment, and a fury of fire that will consume the adversaries...How much worse punishment do you think will be deserved by those who have spurned the Son of God, profaned the blood of the covenant by which they were sanctified, and outraged the Spirit of grace?" (Hebrews 10:26-29)
Another way to examine this situation is, if we imagine that the fig tree can talk (because it represents people), it would be ridiculous if it said "Sorry for being barren, I will do better" and then it continued to be barren.
Even if the fig tree says "Sorry for being barren," it does not change the fact that it will be cut down if it doesn't start producing fruit, no matter how sorry it is. This is why actions reveal whether or not someone has truly repented, because Our Actions Reveal the Truth.
It does not matter what we say if our actions contradict us; it does not matter what we believe if our actions contradict it. What we say and what we believe is revealed by what we do. If we continue to fail to truly repent, then we will perish just as Jesus says.
Only those who actually repent and "produce fruit" (stop being "barren;" stop sinning) will be allowed to "be saved" from being cut down permanently and "thrown into the fire."
For more information on this subject, read about the Meaning of Repentance and Salvation.