Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[77] So being desirous to turn the people to this war against the Ammonites by fear of the losses they should otherwise undergo, and that they might the more suddenly be gathered together, he cut the sinews of his oxen, and threatened to do the same to all such as did not come with their armor to Jordan the next day, and follow him and Samuel the prophet whithersoever they should lead them. So they came together, out of fear of the losses they were threatened with, at the appointed time. And the multitude were numbered at the city Bezek. And he found the number of those that were gathered together, besides that of the tribe of Judah, to be seven hundred thousand, while those of that tribe were seventy thousand. So he passed over Jordan, and proceeded in marching all that night, thirty furlongs, and came to Jabesh before sun-rising. So he divided the army into three companies; and fell upon their enemies on every side on the sudden, and when they expected no such thing; and joining battle with them, they slew a great many of the Ammonites, as also their king Nabash. This glorious action was done by Saul, and was related with great commendation of him to all the Hebrews; and he thence gained a wonderful reputation for his valor: for although there were some of them that contemned him before, they now changed their minds, and honored him, and esteemed him as the best of men: for he did not content himself with having saved the inhabitants of Jabesh only, but he made an expedition into the country of the Ammonites, and laid it all waste, and took a large prey, and so returned to his own country most gloriously. So the people were greatly pleased at these excellent performances of Saul, and rejoiced that they had constituted him their king. They also made a clamor against those that pretended he would be of no advantage to their affairs; and they said, Where now are these men? - let them be brought to punishment, with all the like things that multitudes usually say when they are elevated with prosperity, against those that lately had despised the authors of it. But Saul, although he took the good-will and the affection of these men very kindly, yet did he swear that he would not see any of his countrymen slain that day, since it was absurd to mix this victory, which God had given them, with the blood and slaughter of those that were of the same lineage with themselves; and that it was more agreeable to be men of a friendly disposition, and so to betake themselves to feasting.