What does Judges 9:13 mean?
Jotham, the only surviving sibling of Gideon's seventy sons, other than the man who killed them, is telling a story (Judges 9:8–12). He is presenting a fable about trees searching for a king to make a larger point to the people of Shechem about the king they are anointing on this day: his murderous brother, Abimelech (Judges 9:1–6).In the story, the olive and fig trees declined to rule over the others. Their productivity is already valuable, so they have no desire to seek power over others. Likewise, the grape vine decides that the cheer-inducing wine it makes is too important to leave behind to merely serve as king over the trees.
After being rejected by valuable, capable options, the trees in Jotham's tale turn to something not only useless, but dangerous: the bramble bush. This is a clear attack on Abimelech's fitness to rule (Judges 9:14).