'Be Strong' in the Bible

And behold, Amariah the chief priest is over you in all matters of Jehovah, and Zebadiah the son of Ishmael, prince of the house of Judah, in all the king's matters; and ye have the Levites before you as officers. Be strong and do it, and Jehovah will be with the good.

But if thou wilt go, do it; be strong for the battle: God will make thee fall before the enemy, for there is with God power to help and to cast down.

Be strong and courageous, be not afraid nor dismayed for the king of Assyria, nor for all the multitude that is with him; for there are more with us than with him: