But God had a good reason for inspiring this act of barbarism: he did it to encourage the troops and to terrorize the opposition.
Here's how it happened.
When Judith returned to the Israelites, she took Holofernes' head out of the wallet, and showed it to them, assuring everyone that no sex was involved in the murderous deed.
She brought forth the head of Holofernes out of the wallet, and shewed it them, saying: Behold the head of Holofernes the general of the army of the Assyrians, and behold his canopy, wherein he lay in his drunkenness, where the Lord our God slew him by the hand of a woman. ... The Lord hath not suffered me his handmaid to be defiled. Judith 13:19-20
Achior (an unbelieving Ammonite that happened to be around at the time) had this to say about it.
God ... hath cut off the head of all the unbelievers this night by my hand. Judith 13:27He was, in fact, so impressed with the whole thing that he decided to become a Jew right then and there, cutting off his own foreskin to seal the deal. Glory!
Then Achior seeing the power that the God of Israel had wrought, leaving the religion of the gentiles, he believed God, and circumcised the flesh of his foreskin, and was joined to the people of Israel. Judith 14:6Judith told the Israelites to hang Holofernes' head on the wall and wait a bit until the Assyrians see the headless body of Holofernes wallowing around in his own blood. Then, while they're freaking out about that, attack them while they're running away. God will help them kill them all.
Judith said to all the people: Hear me, my brethren, hang ye up this head upon our walls. ... when the captains of them shall run to the tent of Holofernes, and shall find him without his head wallowing in his blood, fear shall fall upon them.And when you shall know that they are fleeing, go after them securely, for the Lord will destroy them under your feet. Judith 14:1-5So that's what they did. They hung Holofernes' head on the wall. Then they all screamed and took off after the fleeing Assyrian army.
They hung up the head of Holofernes upon the walls, and every man took his arms, and they sent out with a great noise and shouting. Judith 14:7Meanwhile one of the Assyrians went into Holofernes' tent and saw his headless body sweltering in his blood. So he screamed bloody murder and rent his garments.
Vagao ... perceived ... the body of Holofernes, lying upon the ground, without the head, sweltering in his blood, he cried out with a loud voice, with weeping, and rent his garments. Judith 14:14Then he ran out and told all the people.
He ran out to the people, and said, One Hebrew woman hath made confusion in the house of king Nabuchodonosor: for behold Holofernes lieth upon the ground, and his head is not upon him. Judith 14:15-16When the Assyrian chiefs and army heard about that, they did what all biblical characters do in such cases: they tore up their clothes and started screaming.
When the chiefs of the army of the Assyrians had heard this, they all rent their garments ... And there was a very great cry in the midst of their camp. Judith 14:17-18The entire Assyrian army was so shook up by the whole thing that they all ran away.
When all the army heard that Holofernes was beheaded, courage and counsel fled from them, and being seized with trembling and fear they thought only to save themselves by flight. Judith 15:1The Israelites chased them as they ran, killing them all (with God's help, of course) with the edge of the sword.
The children of Israel pursuing in one body, defeated all that they could find ... with the edge of the sword. Judith 15:4-6
How's that for a likely story?