Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
(Jdg 3:1-7) The nations left to prove Israel.
(Jdg 3:8-11) Othniel delivers Israel.
(v. 12-30) Ehud delivers Israel from Eglon.
(Jdg 3:31) Shamgar delivers and judges Israel.
As the Israelites were a type of the church on earth, they were not to be idle and slothful. The Lord was pleased to try them by the remains of the devoted nations they spared. Temptations and trials detect the wickedness of the hearts of sinners; and strengthen he graces of believers in their daily conflict with Satan, sin, and this evil world. They must live in this world, but they are not of it, and are forbidden to conform to it. This marks the difference between the followers of Christ and mere professors. The friendship of the world is more fatal than its enmity; the latter can only kill the body, but the former murders many precious souls.
The first judge was Othniel: even in Joshua's time Othniel began to be famous. Soon after Israel's settlement in Canaan their purity began to be corrupted, and their peace disturbed. But affliction makes those cry to God who before would scarcely speak to him. God returned in mercy to them for their deliverance. The Spirit of the Lord came upon Othniel. The Spirit of wisdom and courage to qualify him for the service, and the Spirit of power to excite him to it. He first judged Israel, reproved and reformed them, and then went to war. Let sin at home be conquered, that worst of enemies, then enemies abroad will be more easily dealt with. Thus let Christ be our Judge and Lawgiver, then he will save us.
When Israel sins again, God raises up a new oppressor. The Israelites did ill, and the Moabites did worse; yet because God punishes the sins of his own people in this world, Israel is weakened, and Moab strengthened against them. If lesser troubles do not do the work, God will send greater. When Israel prays again, God raises up Ehud. As a judge, or minister of Divine justice, Ehud put to death Eglon, the king of Moab, and thus executed the judgments of God upon him as an enemy to God and Israel. But the law of being subject to principalities and powers in all things lawful, is the rule of our conduct. No such commissions are now given; to pretend to them is to blaspheme God. Notice Ehud's address to Eglon. What message from God but a message of vengeance can a proud rebel expect? Such a message is contained in the word of God; his ministers are boldly to declare it, without fearing the frown, or respecting the persons of sinners. But, blessed be God, they have to deliver a message of mercy and of free salvation; the message of vengeance belongs only to those who neglect the offers of grace. The consequence of this victory was, that the land had rest eighty years. It was a great while for the land to rest; yet what is that to the saints' everlasting rest in the heavenly Canaan.
The side of the country which lay south-west, was infested by the Philistines. God raised up Shamgar to deliver them; having neither sword nor spear, he took an ox-goad, the instrument next at hand. God can make those serviceable to his glory and to his church's good, whose birth, education, and employment, are mean and obscure. It is no matter what the weapon is, if God directs and strengthens the arm. Often he works by unlikely means, that the excellency of the power may appear to be of God.