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

[12] But when Bacchides knew that Jonathan had pitched his camp among the lakes of Jordan, he observed when their sabbath day came, and then assaulted him, [as supposing that he would not fight because of the law for resting on that day]: but he exhorted his companions [to fight]; and told them that their lives were at stake, since they were encompassed by the river, and by their enemies, and had no way to escape, for that their enemies pressed upon them from before, and the river was behind them. So after he had prayed to God to give them the victory, he joined battle with the enemy, of whom he overthrew many; and as he saw Bacchides coming up boldly to him, he stretched out his right hand to smite him; but the other foreseeing and avoiding the stroke, Jonathan with his companions leaped into the river, and swam over it, and by that means escaped beyond Jordan while the enemies did not pass over that river; but Bacchides returned presently to the citadel at Jerusalem, having lost about two thousand of his army. He also fortified many cities of Judea, whose walls had been demolished; Jericho, and Emmaus, and Betboron, and Bethel, and Tinma, and Pharatho, and Tecoa, and Gazara, and built towers in every one of these cities, and encompassed them with strong walls, that were very large also, and put garrisons into them, that they might issue out of them, and do mischief to the Jews. He also fortified the citadel at Jerusalem more than all the rest. Moreover, he took the sons of the principal Jews as pledges, and hut them up in the citadel, and in that manner guarded it.