Why does Jesus curse the fig tree? What can be the guilt of a simple tree?
Answer: The answer requires two steps:
1. The importance of symbolic actions of prophets.
The old prophets in the Bible, such as Samuel (1 Samuel 15:27-28), Ahijah the Shilonite (1 Kings 11:29-39), or the false prophet Zedekiah (1 Kings 22:11-12) already used symbolic actions during their prophesying, not so much to impress their listeners more strongly, but because of the effect of these signs: They create a real connection between the signs and the reality they proclaim, so that the proclaimed reality becomes as irrevocable as the accompanying sign. This process can be found with virtually all major prophets of the Old Testament: For example, Hosea’s whole mission is marked by a symbolic act which determines the fate of his life (Hosea 1-30). It is rarer in Isaiah, but compare Isaiah 20 and the symbolic names he gives his children (Isaiah 7:3; compare 10:21); 8:1-4; 8:18). Jeremiah carries out and interprets many symbolic acts and occurrences, and Ezekiel, too, carries out symbolic acts. Like Hosea, he interprets his own trials as symbolic occurrences. Symbolism also occurs in the New Testament, as in the case of the fig tree that is cursed by Jesus (Matthew 21:18-19 and Mark 11:12-14; 20:24).
2. The story of Jesus cursing a fig tree.
As did the prophets in the past, so does Jesus carry out a symbolic act here, whereby the fig tree represents the barren and, therefore, punished land of Israel. If they get enough water and maybe fertilizer, fig trees can also thrive on harsh, stony ground and therefore the barrenness of a fig tree is a justified nuisance. Of course, the point of the story is not to curse a fig tree as though it was a creature with a free will. Nor is it to criticize the people who may not have treated the tree well enough. As with all symbolic acts, the point of the story lies in the purpose of the sign, and this has to do with the listeners lacking of true faith in Jesus. The text in the Gospel of Matthew shows Jesus in punishing strictness.
Reading the parallel section in the Gospel of Mark (11:12-14; 20:24) shows how the author of the Gospel of Mark inserted this story afterward into a context he had been given. He did this in two stages: first came the curse, then the withering – a later addition which was intended to use the curse to make a point about the effectiveness of faithful prayer.