'Be Strong' in the Bible

Thus saith Jehovah of hosts: Let your hands be strong, ye that hear in these days these words by the mouth of the prophets, that were in the day that the foundation of the house of Jehovah of hosts was laid, that the temple might be built.

And it shall come to pass, like as ye were a curse among the nations, O house of Judah and house of Israel, so will I save you, and ye shall be a blessing: fear ye not, let your hands be strong.