1 Samuel 11:6

And the Spirit of God came upon Saul when he heard those tidings, and his anger was kindled greatly.

Saul was coming in from the field with his herds when swift messengers arrived with news of Jabesh-gilead that filled Israel with terror and loud weeping, prompting him to ask why the people wept. What he heard was the shameful Ammonite threat against besieged Jabesh-gilead. The coming of the Spirit of God upon him at hearing those tidings roused all his dormant powers.

When thus roused he stood up as hero and king. The empowering of the Spirit was the same empowering given to Samson. His anger was kindled greatly. He summoned Israel to battle to help the besieged city. To summon the nation he hewed a yoke of oxen in pieces and sent them throughout Israel.

He was only the agent through whom the Lord wrought the deliverance at Jabesh-gilead, so the energy and military skill displayed in the victory came from God. At that time he was still humble and self-distrustful as when first called to the throne, and at first he ascribed the glory to God. The nation's praise for the victory fed his self-confidence, so that afterward he took the honor to himself.