Luke 12-14

Then [Jesus] told this parable: “A man had a fig tree growing in his vineyard, and he went to look for fruit on it but did not find any. So he said to the man who took care of the vineyard, ‘For three years now I’ve been coming to look for fruit on this fig tree and haven’t found any. Cut it down! Why should it use up the soil?’

“‘Sir,’ the man replied, ‘leave it alone for one more year, and I’ll dig around it and fertilize it. If it bears fruit next year, fine! If not, then cut it down.’” (Luke 13:6-9)

In Luke's gospel this parable is told immediately following some conversation about two tragedies--one, the Galilean citizens whose blood Pilate had mixed with sacrifices, and the second, the victims of a tower's collapse at Siloam. If some supposed that these tragedies were brought about by extraordinary sinfulness, then Jesus attempted to dispel their speculations. They were no more sinful than others living in Jerusalem, according to him. Jesus says, in effect, that the appropriate response to news of any tragedy is the searching of one's own soul and repenting of one's own sin.

What's up with the parable of the barren fig tree, then? I believe it's the lesson of fruitfulness. The fig tree is allowed to grow as long as it bears fruit or as long as there is hope that it will bear fruit. Jesus may be saying that God has given us life, that the purpose of our living is to bear the fruit of godliness, and that the time period for bearing such fruit is limited. 

I hope Jesus is not threatening to foreshorten our lives for lack of fruitfulness, and I don't believe he is doing so. In my opinion he is simply pointing to humans' limited spans of life and encouraging us to make the most of our opportunities while we have the chance to do so.