People who do wrong try hard to avoid any punishment. Expensive lawyers are employed to help avoid or minimize punishment but in the days of Jesus, people were expected to recognise that God was involved in causing events which brought punishment for their sins. Old Testament prophets repeatedly made this point. In Ezekiel 17 the prophet is to tell a parable about two eagles and a vine, and then say, “Do you not know what these things mean? … behold the king of Babylon came to Jerusalem … that the kingdom might be humble … and keep his (God’s) covenant that it might stand. But he rebelled …” (verses 12,14,15).
There comes a point when God acts because the people are fixed in their godless ways, although He keeps showing mercy to individuals. In the end God brought destruction on Jerusalem because of the abundance of their sins and lack of repentance. Years later Jesus weeps over Jerusalem because he could see this was going to happen again (Luke 13:34,35). Jesus is agonising over the future of the people. Earlier (verse 4) it was thought that the collapsed tower which killed 18 people meant they must have been worse sinners than others. How did Jesus respond? “No” he says, and “I tell you; but unless you repent you will all likewise perish”. If we are not on God’s side, trying to do His will, there is no future for us (remember Luke 11:23).
Jesus followed up his warning with a parable about a man who planted a tree (verses 6-9); for 3 years he looked for fruit, but found none. It was given one more year to produce fruit and a special effort was made to fertilise it. If it did not produce fruit it would be destroyed. Jesus made a special effort to fertilise the tree of Israel (Matthew 15:24). Most would not heed; those who did were largely the common people who “heard him gladly”. Forty years later there was terrible destruction.
Now that “the times of the Gentiles” are at an end, the same grim warning applies to us! “Unless you repent you will …”