"Have you not known?
Have you not heard, that the everlasting God,
the LORD, the Creator of the ends of the earth,
faints not, neither is weary?
there is no searching of his understanding.
He gives power to the faint;
and to them that have no might
he increases strength.
Even the youths will faint and be weary,
and the young men will utterly fall:
But those who wait upon the LORD
will renew their strength;
they will mount up with wings like eagles;
they will run, and not be weary;
and they will walk, and not faint."
(Isaiah 40:28-31 AKJV)