Yiftach (Jephthah) was a great military strategist but he was one of the most flawed of our nation’s Judges. The Talmud (Baba Kama 92b) wishes to illustrate the point that “a tree bearing bad fruit travels among barren trees” (i.e., likeminded people gather together). One of its proofs is this verse, in which “empty” people were attracted to Yiftach.