What does Judges 9:21 mean?
Jotham made his surprise speech at Abimelech's coronation (Judges 9:7). He has told his fable (Judges 9:8–15) and pronounced his curse upon both Abimelech and the people of Shechem (Judges 9:16–20). He rightly condemns them for the murder of his brothers, for dishonoring Gideon's legacy, and for their cynical choice of a worthless king (Judges 9:1–6). Now Jotham runs away.This is not simple cowardice on Jotham's part. He's described as the youngest son of Gideon (Judges 9:5), he has no army, and Shechem has shown willingness to engage in open murder. Abimelech would have wanted to kill Jotham for several reasons. The young man has cast a shadow over the beginning of his reign as king of Shechem. Worse, if any other sons of Gideon live, Abimelech's position as the sole heir of Gideon's authority is subject to challenge.
Jotham was strategic in choosing the place from which to confront the people of Shechem. From on top of Mount Gerizim, he could simply run in the other direction. His choice of a mountain ledge would have allowed him to shout out his words and escape before being caught. Abimelech may have pursued Jotham, but he escaped to a place identified as "Be'er" and remained there so long as necessary to stay out of Abimelech's reach. No exact location is known for "Be'er," but the name refers to a well of water.