Verses 1-2, Abimelech goes to one of the chief cities in the tribe of Ephraim–Shechem–and tries to convince the elders of the tribe to set him up as king as opposed to his 70 brothers. Abimelech sites his mother’s heritage and claims to be one of their own.
–Note that there is no mention of Gideon’s other sons trying to rule. We are apt to see the evil in others that is present in our own lives. Mt. 7:1-5
Verses 3-6, Here we see idolatry, cruelty, and vain character all in the name of Baalberith and Abimelech. The heartless murder of Gideon’s sons is at the center of Abimelech’s kingship and the men of Shechem help.
Verses 7-21, Here we have a fable from the one surviving son of Gideon. He preaches during the coronation celebration and offers his fable as God’s Word. In the fable the trees are seeking a king and those that are worthy reject the trees offer; knowing there place to serve. Only the worthless bramble accepts. See Num. 33:55; Josh. 32:13; Jud. 2:3.
Jotham claims in the end that if they did right God would bless, but if not God would allow the men of Shechem and Abimelech to consume one another.
Verses 22-41, Abimelech’s rule turns out to be less than satisfactory after three years and the men of Shechem turn on him; specifically at the arrival of Gaal. Gaal’s boastful claims are overheard and eventually put to the test. Prov. 16:18.
Verses 42-55, With Gaal defeated and out of the way Abimelech goes on a rampage to destroy all those that rose against him. In the end, his head is literally crushed by a woman. Sadly, even in his dying breath, there is no concern for his soul but only his pride.
Verses 56-57, These verses give us the basic lesson. God will always be sovereign and just; He will even use the evil to destroy evil. God will always put down pride.
Two practical lesson for us. See 1 Tim. 5:22 and James 4:6-10.