“the land of Tob.” The identity of this area is uncertain, but it is most likely just out of Gilead to the north or northeast in the area of Bashan. Ironically, the area is called “Tob” (or Tov), “good,” but it was apparently not normally a good place to live, being adjacent to pagan lands and open to attacks and marauders. In spite of his circumstance, and in some respects due to them, Jephthah learned to rely on Yahweh and sharpened his fighting skills. He could fight off enemies and also attack to the north, east, or south without attacking Israel and fighting Israelites. The “worthless fellows” he gathered around him may have been worthless from the world’s point of view, but they became an excellent fighting force.
“empty men.” The meaning of the Hebrew is unclear and debated. It is literally, “empty men,” but that could easily mean that they were men like Jephthah himself, who had no good name and no land. This very much anticipates the men who joined David (1 Sam. 22:1-2). This does not mean that the men were ungodly or unprincipled. The men who followed David were in debt, discontented, etc., and could be referred to as “empty” from a social point of view. David also went out on raids when he was in the same situation.
“went out with him on raids.” This is where Jephthah would have gotten his reputation as a warrior. He could well have been raiding the enemies of Israel.