Eglon was a very fat man - The איש בריא ish bari of the text is translated by the Septuagint ανηρ αστειος σφοδρα, a very beautiful or polite man, and in the Syriac, a very rude man. It probably means what we call lusty or corpulent.

And he brought a present unto Eglon king of Moab,.... Accompanied by two servants, as Josephus says (b), and who doubtless bore the presents; for that there were such with him that did is clear from Judges 3:18; nor can it be thought that so great a personage as a judge in Israel should go alone and carry a present in his own hands; though it is possible, when come to the king of Moab, he might take it from his servants, and deliver it to him with his own hands:

and Eglon was a very fat man: and so the less active, and unable to decline and avoid the stroke, he might see, when about to be given him.

(b) Antiqu. l. 5. c. 4. sect. 2.

Provided with this weapon, he brought the present to king Eglon, who - as is also mentioned as a preparation for what follows - was a very fat man.

And he brought the present unto Eglon king of Moab: and Eglon was a very fat man.

3:17 The present - Which was to be paid to him as a part of his tribute.

3:12-30 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.