'Enemy' in the Bible

And if thy people Israel be put to the worse before the enemy, because they have sinned against thee; and shall return and confess thy name, and pray and make supplication before thee in this house;

But if thou wilt go, do it, be strong for the battle: God shall make thee fall before the enemy: for God hath power to help, and to cast down.

And under their hand was an army, three hundred thousand and seven thousand and five hundred, that made war with mighty power, to help the king against the enemy.