'Be Strong' in the Bible

And now, Amariah, the chief priest, is over you in all questions to do with the Lord; and Zebadiah the son of Ishmael, the head of the family of Judah, in everything to do with the king's business; and the Levites will be overseers for you. Be strong to do the work; and may the Lord be with the upright.

But go yourself, and be strong in war; God will not let you go down before those who are fighting against you; for God has power to give help or to send you down before your attackers.

In addition, he gave orders to the people of Jerusalem to give to the priests and Levites that part which was theirs by right, so that they might be strong in keeping the law of the Lord.

Be strong and take heart; have no fear, and do not be troubled on account of the king of Assyria and all the great army with him: for there is a greater with us.